DCTC13 book FINALE · NMR spectroscopy and accurate first principle calculations 17:15-17:30 Lucas...

II Congresso della Divisione di Chimica Teorica e Computazionale della SCI – Padova 20-22.02.2013

I

DCTC13

II Congresso Nazionale della Divisione di Chimica Teorica e Computazionale della

Società Chimica Italiana

20-22 febbraio 2013 Padova, Centro Culturale ‘San Gaetano’

Comitato Scientifico

GIANFRANCO PACCHIONI (Univ. Milano Bicocca, Presidente DCTC-SCI) ORLANDO CRESCENZI (Univ. Napoli “Federico II”) DARIO DUCA (Univ. Palermo) LUCIANA MARINELLI (Univ. Napoli “Federico II”) ANTONINO POLIMENO (Univ. Padova) FABRIZIO SANTORO (ICCOM-CNR, Pisa) MAURO STENER (Univ. Trieste) MAURIZIO CASARIN (Univ.Padova)

Comitato Organizzatore ALESSANDRO BAGNO (Univ. Padova) MAURIZIO CASARIN (Univ. Padova) ALBERTA FERRARINI (Univ. Padova) DANIEL FORRER (Univ. Padova) DIEGO FREZZATO (Univ. Padova) GIORGIO J. MORO (Univ. Padova) LAURA ORIAN (Univ. Padova) GIULIA PARISIO (Univ. Padova) ANTONINO POLIMENO (Univ. Padova) GIACOMO SAIELLI (Univ. Padova) MAURO STENER (Univ. Trieste)

Segreteria E-mail: [email protected]

Sito web http://www.chimica.unipd.it/dctc13


II

Università degli Studi di Padova

CNR Padova

Dipartimento di

Scienze Chimiche

Con la sponsorizzazione di

Hewlett Packard

E4 Computer Engineering


III

PROGRAMMA

Mercoledì 20 Febbraio

14:15-14:30 Apertura del Congresso (G. Pacchioni, U. Milano Bicocca, Presidente DCTC della SCI)

Sessione 1

Chairman: A. Polimeno (Dip. di Scienze Chimiche, Padova)

14:30-15:00 Invited: Gianfranco Tantardini Dip. di Chimica Fisica ed Elettrochimica, U. Milano Theoretical studies of C-based nanostructures

15:00-15:15 Enrico Bodo (U. “La Sapienza”) The structure of ionic liquids from a molecular perspective: recent theoretical and experimental results

15:15-15:30 Claudio Greco (U. Milano Bicocca) DFT-based design of molecular functionality: the case of hydrogenases biomimetic models

15:30-15:45 Daniele Toffoli (Middle East Technical University) Density functional theory for molecular multiphoton ionization in the perturbative regime

15:45-16:00 Giuseppe Suffritti (U. Sassari) Structure and dynamics of hydrated Na vermiculite clay studied by Car-Parrinello molecular dynamics simulations

16:00-16:30 Coffee Break

Sessione 2

Chairman: F. Santoro (ICCOM-CNR, Pisa)

16:30-17:00

Invited – Benedetta Mennucci (ERC Starting Grant) Dip. di Chimica e Chimica Industriale, U. Pisa The interplay between environment and excited state processes in (supra)molecular systems: a quantum chemical picture

17:00-17:15 Livia Giordano (U. Milano Bicocca) Charging of gold atoms on doped MgO and CaO: identifying the key parameters by DFT calculations

17:15-17:30 Tiziana Marino (U. Calabria) Catalytic mechanism of the arylsulfatase promiscuous enzyme

17:30-17:45 Vincenzo Villani (U. Basilicata) H-transfer termination mechanisms in polyolefin homogeneous catalysis

17:45-18:00 Anna Ferrari ( U. Torino ) Modified ion pair interaction for water dimers on supported MgO ultrathin films

18:00-19:00 Poster session


IV

Giovedì 21 Febbraio

Sessione 3

Chairman: M. Stener (Dip. Scienze Chimiche e Farmaceutiche, Trieste)

09:00- 09:30

Invited – Emilia Sicilia Dip. di Chimica, U. della Calabria (Cosenza) Catalytic generation of hydrogen assisted by metal-based homogeneous catalysts: computational insights

09:30- 09:45 Antonio Laganà ( U. Perugia ) Towards a Virtual Research Community for chemistry, molecular and materials science and technology

09:45- 10:00 Filippo Lipparini ( U. Pierre et Marie Curie ) A very fast divide and conquer discretization algorithm for the Polarizable Continuum Model

10:00-10:15 Anna Painelli ( U. Parma ) Tuning the nature of the fluorescent state: a substituted polycondensed dye as a case study

10:15-10:30 Giosuè Costa ( U. Catanzaro ) Identification and characterization of new DNA G-Quadruplex binders selected by a combination of ligand and structure-based virtual screening approaches


Sessione 4

Chairman: A. Laganà (Dip. Chimica, Perugia)

11:00-11:30

Invited – Sonia Coriani Dip. Scienze Chimiche, U. Trieste Correlated response methods to model absorption, ionization and scattering phenomena

11:30-11:45 Michele Pavone ( U. “Federico II” ) Ab-initio DFT+U Study of Sr-doped LaMO3 (M=Cr, Mn)

11:45-12:00 Nazzareno Re ( U. “D’Annunzio” ) Computational investigation of IR spectra of electrospray ionized biomolecules

12:00-12:15

Alessandro Biancardi ( U. Pisa ) An investigation of the photophysical properties of minor groove bound and intercalated molecular probes for nucleic acids, through QM and spectroscopic tools

12:15-12:30 Davide Presti ( U. Modena-Reggio Emilia ) Benchmarking periodic dispersion-corrected DFT calculations for the prediction of molecular crystal polymorphism

12:30-14:30 Pausa


V

Sessione 5

Chairman: O. Crescenzi (Dip. di Chimica, Napoli)

14:30-15:00

Invited – Anna Bernardi Dip. di Chimica Organica ed Industriale, U. Milano Design of mono- and polyvalent mimics of oligosaccharides

15:00-15:15

Emanuele Coccia ( U. L’Aquila ) Protein field effect on the dark state of 11-cis Retinal in Rhodopsin by Quantum Monte Carlo/Molecular Mechanics

15:15-15:30

Roberto Orlando ( U. Torino ) Massively parallel CRYSTAL program for large unit cell ab initio calculations

15:30-15:45

Cecilia Coletti ( U “D’Annunzio” ) Coulomb Sturmian Orbitals and Hyperspherical Harmonics as building blocks for quantum chemical applications

15:45-16:00

Ivan Carnimeo ( Scuola Normale Superiore di Pisa ) DFTB/PCM and TD-DFTB/PCM approaches for calculation of spectroscopical properties of large systems in solution

16:00-16:30

Coffee Break

Sessione 6

Chairman: D. Duca (Dip. di Fisica e Chimica, Palermo)

16:30-17:00

Invited – Andrea Vittadini ISTM-CNR Padova Structure and reactivity of metal-supported self-assembled molecular layers from first principles

17:00-17:15

Elisa Gambuzzi ( U. Modena Reggio Emilia ) Silicate and aluminosilicate glasses: probing network arrangement by solid state NMR spectroscopy and accurate first principle calculations

17:15-17:30

Lucas Viani ( U. Pisa ) Spatial and Electronic Correlations in the PE545 Light-Harvesting Complex

17:30-17:45

Fabio Grassi ( U. Piemonte Orientale ) A First Principles Study of Capping Energies and Electronic States in PbSe Nanocrystals

17:45-18:00

Remedios Cortese ( U. Palermo ) Selective hydrogenation of 2-methyl-3-butyn-2-ol on Pd catalysts

18:00-19:00

Poster session

19:00-20:00

Assemblea della Divisione


VI

Venerdì 22 Febbraio

Sessione 7

Chairman: M. Casarin (Dip. di Scienze Chimiche, Padova)

09:00-09:30

Invited - Francesco Tarantelli Dip. di Chimica, U. Perugia Charge displacement analysis: a different view of bonding, from non-covalent interactions to coordination chemistry

09:30-09:45 Oliviero Andreussi ( U. Pisa ) Self-consistent continuum solvation (SCCS) in periodic electronic-structure calculations

09:45-10:00 Ana Belen Munoz Garcia ( U. “Federico II” ) Unveiling structure-property relationships in Perovskite-oxide based electrodes for solid oxide fuel cell applications

10:00-10:15 Marco De La Pierre ( U. Torino ) Ab initio simulation as the key tool to interpret the IR reflectance spectra of crystalline solids

10:15-10:30 Simone Casolo ( U. Milano ) Eley-Rideal hydrogen recombination on graphite: ab-inito molecular dynamics of an astrophysical gas-surface reaction


Sessione 8

Chairman: L. Marinelli (Dip. di Chimica Farmaceutica, Napoli)

11:00-11:30 Invited - Alessandro Fortunelli IPCF-CNR Pisa Global optimization methods in chemistry

11:30-11:45 David Picconi ( Technische Universitaet Muenchen ) A strategy for nonadiabatic quantum-classical dynamics of semirigid molecules. Investigating the photostability of nucleobases

11:45-12:00 Alessandro Erba ( U. Torino ) Ab initio temperature effect on one-electron properties of solids

12:00-12:15 Elisa Frezza ( U. Padova ) The phase diagram of hard helices: classical DFT and Monte Carlo simulations

12:15-12:30 Leonardo Belpassi ( ISTM-CNR Perugia ) Recent advances and perspectives in 4-component Dirac-Kohn-Sham calculations

12:30-14:15 Pausa

Sessione 9

Chairman: G. Pacchioni (Dip. di Scienza dei Materiali, Milano Bicocca)

14:15-14:45 Invited - Maurizio Recanatini Dip. di Farmacia e Biotecnologie, U. Bologna Computational studies on the hERG potassium channel


VII

14:45-15:15

Invited - Chiara Cappelli (Medaglia Roetti) Scuola Normale Superiore, Pisa Bridging the gap between theory and experiment: modeling solvent effects on molecular properties and spectroscopies

15:15-15:45

Invited - Alfonso Pedone (Targa Scrocco) Dip. di Scienze Chimiche e Geologiche, U. Modena e Reggio Emilia Computational simulations of solid state NMR spectra: a new era in structure determination of oxide glasses

15:45-16:15 Invited - Vincenzo Barone (ERC Advanced Grant) Scuola Normale Superiore, Pisa Toward a multifrequency virtual spectrometer


VIII


IX

SOMMARIO

INVITED LECTURES

TOWARD A MULTIFREQUENCY VIRTUAL SPECTROMETER ............................... 3

Vincenzo Barone

DESIGN OF MONO- AND POLYVALENT MIMICS OF OLIGOSACCHARIDES........ 4

Anna Bernardi

BRIDGING THE GAP BETWEEN THEORY AND EXPERIMENT: MODELING SOLVENT EFFECTS ON MOLECULAR PROPERTIES AND SPECTROSCOPIES . 5

Chiara Cappelli

CORRELATED RESPONSE METHODS TO MODEL ABSORPTION, IONIZATION AND SCATTERING PHENOMENA............................................................................ 6

Sonia Coriani

GLOBAL OPTIMIZATION METHODS IN CHEMISTRY ............................................. 7

Alessandro Fortunelli

THE INTERPLAY BETWEEN ENVIRONMENT AND EXCITED STATE PROCESSES IN (SUPRA)MOLECULAR SYSTEMS: A QUANTUM CHEMICAL PICTURE.................................................................................................................... 9

Benedetta Mennucci

THEORETICAL STUDIES OF C-BASED NANOSTRUCTURES ............................. 10

Rocco Martinazzo, Matteo Bonfanti, Simone Casolo, Gian Franco Tantardini

COMPUTATIONAL SIMULATIONS OF SOLID STATE NMR SPECTRA: A NEW ERA IN STRUCTURE DETERMINATION OF OXIDE GLASSES ............................ 11

Thibault Charpentier, Maria Cristina Menziani, Alfonso Pedone

COMPUTATIONAL STUDIES ON THE hERG POTASSIUM CHANNEL................. 12

Maurizio Recanatini, Matteo Masetti

CHARGE DISPLACEMENT ANALYSIS: A DIFFERENT VIEW OF BONDING, FROM NON-COVALENT INTERACTIONS TO COORDINATION CHEMISTRY................. 13

Francesco Tarantelli


X

CATALYTIC GENERATION OF HYDROGEN ASSISTED BY METAL-BASED HOMOGENEOUS CATALYSTS: COMPUTATIONAL INSIGHTS ............................ 14

Emilia Sicilia, Valeria Butera, Nino Russo

STRUCTURE AND REACTIVITY OF METAL-SUPPORTED SELF-ASSEMBLED MOLECULAR LAYERS FROM FIRST PRINCIPLES ............................................... 15

Andrea Vittadini

COMUNICAZIONI ORALI

SELF-CONSISTENT CONTINUUM SOLVATION (SCCS) IN PERIODIC ELECTRONIC-STRUCTURE CALCULATIONS....................................................... 19

Oliviero Andreussi, Nicola Marzari

AN INVESTIGATION OF THE PHOTOPHYSICAL PROPERTIES OF MINOR GROOVE BOUND AND INTERCALATED MOLECULAR PROBES FOR NUCLEIC ACIDS, THROUGH QM AND SPECTROSCOPIC TOOLS ...................................... 20

Alessandro Biancardi, Tarita Biver, Benedetta Mennucci

THE STRUCTURE OF IONIC LIQUIDS FROM A MOLECULAR PERSPECTIVE: RECENT THEORETICAL AND EXPERIMENTAL RESULTS .................................. 21 E. Bodo, R. Caminiti

DFTB/PCM AND TD-DFTB/PCM APPROACHES FOR CALCULATION OF SPECTROSCOPICAL PROPERTIES OF LARGE SYSTEMS IN SOLUTION ......... 22

Carnimeo I., Scalmani G., Barone V.

PROTEIN FIELD EFFECT ON THE DARK STATE OF 11-CIS RETINAL IN RHODOPSIN BY QUANTUM MONTE CARLO/MOLECULAR MECHANICS .......... 23

Emanuele Coccia, Daniele Varsano , Leonardo Guidoni

COULOMB STURMIAN ORBITALS AND HYPERSPHERICAL HARMONICS AS BUILDING-BLOCKS FOR QUANTUM CHEMICAL APPLICATIONS....................... 24

Cecilia Coletti, Danilo Calderini, Vincenzo Aquilanti

SELECTIVE HYDROGENATION OF 2-METHYL-3-BUTYN-2-OL ON Pd CATALYSTS............................................................................................................. 25

Remedios Cortese, Francesco Ferrante, Antonio Prestianni, Dario Duca

IDENTIFICATION AND CHARACTERIZATION OF NEW DNA G-QUADRUPLEX BINDERS SELECTED BY A COMBINATION OF LIGAND AND STRUCTURE-BASED VIRTUAL SCREENING APPROACHES ..................................................... 26

Costa G., Alcaro S., Musetti C., Distinto S., Casatti M., Zagotto G., Artese A., Parrotta L., Moraca F., Ortuso F.,

Maccioni E., Sissi C.


XI

AB INITIO SIMULATION AS THE KEY TOOL TO INTERPRET THE IR REFLECTANCE SPECTRA OF CRYSTALLINE SOLIDS........................................ 28

M. De La Pierre, C. Carteret, R. Dovesi

AB INITIO TEMPERATURE EFFECT ON ONE-ELECTRON PROPERTIES OF SOLIDS .................................................................................................................... 29

Alessandro Erba, Cesare Pisani, Matteo Ferrabone, Roberto Dovesi

MODIFIED ION PAIR INTERACTION FOR WATER DIMERS ON SUPPORTED MgO ULTRATHIN FILMS.................................................................................................. 30

Anna Maria Ferrari, Livia Giordano

THE PHASE DIAGRAM OF HARD HELICES: CLASSICAL DFT AND MONTE CARLO SIMULATIONS............................................................................................ 31

Elisa Frezza, Alberta Ferrarini, Hima Bindu Kolli, Achille Giacometti, Giorgio Cinacchi

SILICATE AND ALUMINOSILICATE GLASSES: PROBING NETWORK ARRANGEMENT BY SOLID STATE NMR SPECTROSCOPY AND ACCURATE FIRST PRINCIPLE CALCULATIONS....................................................................... 32

Elisa Gambuzzi, Alfonso Pedone, Maria Cristina Menziani, Thibault Charpentier

CHARGING OF GOLD ATOMS ON DOPED MgO AND CaO: IDENTIFYING THE KEY PARAMETERS BY DFT CALCULATIONS....................................................... 34

Livia Giordano, Stefano Prada, Gianfranco Pacchioni

A FIRST PRINCIPLES STUDY OF CAPPING ENERGIES AND ELECTRONIC STATES IN PbSe NANOCRYSTALS ....................................................................... 35

Fabio Grassi, Mario Argeri, Lorenzo Canti, Maurizio Cossi, Alberto Fraccarollo, Leonardo Marchese

DFT-BASED DESIGN OF MOLECULAR FUNCTIONALITY: THE CASE OF HYDROGENASES BIOMIMETIC MODELS............................................................. 36

Claudio Greco, Maurizio Bruschi, Piercarlo Fantucci, Luca De Gioia

TOWARDS A VIRTUAL RESEARCH COMMUNITY FOR CHEMISTRY, MOLECULAR AND MATERIALS SCIENCE AND TECHNOLOGIES....................... 37

Antonio Laganà, Alessandro Costantini

A VERY FAST DIVIDE AND CONQUER DISCRETIZATION ALGORITHM FOR THE POLARIZABLE CONTINUUM MODEL .................................................................... 39

Filippo Lipparini, Benjamin Stamm, Eric Cancès,Yvon Maday, Benedetta Mennucci

CATALYTIC MECHANISM OF THE ARYLSULFATASE PROMISCUOUS ENZYME................................................................................................................................. 40

Tiziana Marino, Nino Russo


XII

UNVEILING STRUCTURE-PROPERTY RELATIONSHIPS IN PEROVSKITE-OXIDE BASED ELECTRODES FOR SOLID OXIDE FUEL CELL APPLICATIONS............. 41

Ana B. Muñoz-García, Michele Pavone, Emily A. Carter

MASSIVELY PARALLEL CRYSTAL PROGRAM FOR LARGE UNIT CELL AB INITIO CALCULATIONS...................................................................................................... 42

Roberto Orlando

TUNING THE NATURE OF THE FLUORESCENT STATE: A SUBSTITUTED POLYCONDENSED DYE AS A CASE STUDY........................................................ 43

Cristina Sissa, Valentina Calabrese, Marco Cavazzini, Luca Grisanti, Francesca Terenziani, Silvio Quici, Anna Painelli

AB-INITIO DFT+U STUDY OF Sr-DOPED LaMO3 (M=Cr, Mn)................................ 44

Michele Pavone, Ana B. Muñoz-Garcia, Emily A. Carter

A STRATEGY FOR NONADIABATIC QUANTUM-CLASSICAL DYNAMICS OF SEMIRIGID MOLECULES. INVESTIGATING THE PHOTOSTABILITY OF NUCLEOBASES....................................................................................................... 45

David Picconi, Francisco José Avila Ferrer,Roberto Improta, Alessandro Lami, Fabrizio Santoro

BENCHMARKING PERIODIC DISPERSION-CORRECTED DFT CALCULATIONS FOR THE PREDICTION OF MOLECULAR CRYSTAL POLYMORPHISM.............. 47

Davide Presti, Alfonso Pedone, Maria Cristina Menziani

COMPUTATIONAL INVESTIGATION OF IR SPECTRA OF ELECTROSPRAY IONIZED BIOMOLECULES...................................................................................... 49

Roberto Paciotti, Cecilia Coletti, Nazzareno Re, Maria Elisa Crestoni, Simonetta Fornarini

STRUCTURE AND DYNAMICS OF HYDRATED Na VERMICULITE CLAY STUDIED BY CAR-PARRINELLO MOLECULAR DYNAMICS SIMULATIONS ........................ 50

Giuseppe B. Suffritti, Pierfranco Demontis, Marco Masia

DENSITY FUNCTIONAL THEORY FOR MOLECULAR MULTIPHOTON IONIZATION IN THE PERTURBATIVE REGIME..................................................... 51

Daniele Toffoli, Piero Decleva

SPATIAL AND ELECTRONIC CORRELATIONS IN THE PE545 LIGHT-HARVESTING COMPLEX........................................................................................ 52

Lucas Viani, Carles Curutchet, Benedetta Mennucci

H-TRANSFER TERMINATION MECHANISMS IN POLYOLEFIN HOMOGENEOUS CATALYSIS.............................................................................................................. 53

Vincenzo Villani, Gaetano Giammarino


XIII

POSTER

P01 FULLY AUTOMATED PROCEDURE TO EVALUATE ELASTIC AND PIEZOELECTRIC CONSTANTS.............................................................................. 57

Elisa Albanese, Alessandro Erba, Bartolomeo Civalleri

P02 DFT AND TDDFT STUDY OF UNSYMMETRICAL SQUARAINES ADSORBED ON PbSe SURFACES.............................................................................................. 58

Mario Argeri, Claudia Barolo, Maurizio Cossi, Fabio Grassi, Leonardo Marchese

P03 MODELING OF SPIRAL HALLOYSITE NANOTUBES ................................... 60

Francesco Ferrante, Nerina Armata, Giuseppe Lazzara, Stefana Milioto

P04 IMPROVING THE COMPARISON OF COMPUTATIONAL DATA WITH EXPERIMENTAL ABSORPTION AND EMISSION SPECTRA. BEYOND THE VERTICAL TRANSITION APPROXIMATION........................................................... 61

Francisco Avila, Javier Cerezo, Emiliano Stendardo, Roberto Improta, Fabrizio Santoro

P05 BERYLLIUM OXIDE NANOTUBES AND THEIR CONNECTION TO THE FLAT MONOLAYER........................................................................................................... 62

J. Baima, A. Erba, M. Rérat, R. Orlando, R. Dovesi

P06 THE NEAR-EDGE X-RAY-ABSORPTION FINE-STRUCTURE OF O2 CHEMISORBED ON Ag(110) SURFACE STUDIED BY DENSITY FUNCTIONAL THEORY................................................................................................................... 63

Oscar Baseggio, Mauro Stene, Michele Romeo, Giovanna Fronzon

P07 FUNCTIONAL EFFECTS ON THE TDDFT INVESTIGATIONS IN ORGANOMETALLIC PHOTOCHEMISTRY ............................................................. 64

Luca Bertini, Maurizio Bruschi, Claudio Greco, Luca De Gioia, Piercarlo Fantucci, Giuseppe Zampella

P08 STUDY OF THE SPECIATION OF THE [Cu(HGGG)(Py)] COMPLEX IN WATER SOLUTION USING DFTB AND DFT APPROACHES ................................ 65

Maurizio Bruschi, Luca Bertini, Vlasta Bonačić-Koutecký, Luca De Gioia, Roland Mitrić, Giuseppe Zampella,

Claudio Greco, Piercarlo Fantucci

P09 ARE THE NONADIABATIC TRANSITION RATES TRANSFERABLE AMONG DIFFERENT ENVIRONMENTS?.............................................................................. 66

Valentina Cantatore, Giovanni Granucci, Maurizio Persico

P10 THEORETICAL ADSORPTION OF METHANE, HYDROGEN AND CARBON DIOXIDE IN POROUS AROMATIC FRAMEWORKS (PAFs)................................... 68

L. Canti, A. Fraccarollo, M. Cossi, L. Marchese


XIV

P11 THEORETICAL INVESTIGATIONS OF SRTI1-XMXO3-δ (M = Co, Ni, Cu) DOPED-PEROVSKITE SYSTEMS: EFFECTS OF THE DOPING ON THE FORMATION OXYGEN VACANCIES ...................................................................... 70

Silvia Carlotto, Andrea Vittadini, Antonella Glisenti, Marta Maria Natile

P12 ASSESSMENT OF THE GEOMETRICAL CORRECTION FOR THE BSSE IN DFT CALCULATIONS FOR MOLECULAR CRYSTALS .......................................... 71

B. Civalleri, M. Alessio

P13 AB INITIO MODELING OF METAL-ORGANIC FRAMEWORKS: INSIGHTS ON STRUCTURE-PROPERTY RELATIONSHIPS......................................................... 72

B. Civalleri, E. Albanese, L. Valenzano, R. Orlando

P14 AB INITIO SIMULATION OF SPECTROSCOPIC AND OPTICAL PROPERTIES OF NOVEL POROUS GRAPHENE PHASES .......................................................... 73

M. De La Pierre, P. Karamanis, J. Baima, R. Dovesi

P15 AB INITIO MÖSSBAUER ISOMER SHIFT AND QUADRUPOLE SPLITTINGS OF 57Fe WITH CRYSTAL ......................................................................................... 74

S. Casassa, A. M. Ferrari

P16 DESIGN OF NOVEL WO3-BASED MATERIALS WITH TAILORED OPTICAL AND PHOTO-REDOX OR CATALYTIC PROPERTIES ........................................... 75

Cristiana Di Valentin, Fenggong Wang, Massimo Rosa, Gianfranco Pacchioni

P17 COMPETITIVE SOLVATION OF K+ BY C6H6 AND H2O IN THE K+-(C6H6)n-(H2O)m (n=1-4; m= 1-6) AGGREGATES................................................................... 76

Noelia Faginas Lago, M. Albertí

P18 COMPUTATIONAL APPROACHES EMPLOYED IN THE SusFuelCat PROJECT................................................................................................................. 77

Francesco Ferrante, Nerina Armata, Remedios Cortese, Fabrizio Lo Celso, Antonio Prestianni, Dario Duca

P19 CHEMICAL REACTION BETWEEN AMINO-FUNCTIONALIZED PORPHYRIN AND CYANURIC CHLORIDE ON SILVER: A STM/DFT STUDY............................. 78

Daniel Forrer, Marco Di Marino, Francesco Sedona, Mauro Sambi, Andrea Vittadini, Maurizio Casarin

P20 MOLECULAR SIMULATION OF H2 AND CH4 ADSORPTION IN POROUS DIPEPTIDE CRYSTALS........................................................................................... 79

Alberto Fraccarollo, Maurizio Cossi, Angiolina Comotti, Leonardo Marchese

P21 TOWARDS BULK THERMODYNAMICS VIA NONEQUILIBRIUM METHODS: THE COMPRESSIBILITY FACTOR OF GASEOUS METHANE AS CASE STUDY. 80

Mirco Zerbetto, Diego Frezzato


XV

P22 EFFECT OF TERMINAL OLIGO(ETHYLENE GLYCOL) ON THE STRUCTURE OF ALKYLTHIOL SAMs: A MOLECULAR DYNAMICS INVESTIGATION ............... 81

Piero Gasparotto, Giulia Parisio, Alberta Ferrarini

P23 QUANTITATIVE STRUCTURE-ACTIVITY RELATIONSHIPS MODELLING AND PREDICTION OF ORGANIC POLLUTANTS BEHAVIOUR IN THE ENVIRONMENT ....................................................................................................... 82

Paola Gramatica, Stefano Cassani, Nicola Chirico, Simona Kovarich, Ester Papa

P24 MODELLING OF THE ELECTROOPTICAL PROPERTIES OF LIQUID CRYSTALS: THE MOLECULAR ORIGIN OF THE ELECTROCLINIC EFFECT ...... 83

Cristina Greco, Alberta Ferrarini

P25 REFINEMENT AND VALIDATION OF THE AMBER FORCE FIELD FOR α, α DIALKYLATED PEPTIDES....................................................................................... 84

Sonja Grubisic, Giuseppe Brancato, Vincenzo Barone

P26 DIELECTRIC NLO PROPERTIES OF POLYACETYLENE.............................. 85

R. Dovesi, M. Ferrabone, M. Ferrero, B. Kirtman, V. Lacivita, R. Orlando, M. Rérat

P27 AB INITIO INVESTIGATION OF ELECTRONIC AND VIBRATIONAL CONTRIBUTIONS TO NONLINEAR DIELECTRIC PROPERTIES OF ICE ............. 86

A. Mahmoud, J. Baima, S. Casassa

P28 ELECTRONIC PROPERTIES OF H2Pc AND CuPc FILMS: AN EXPERIMENTAL AND THEORETICAL STUDY................................................................................... 87

Giulia Mangione, Maurizio Casarin, Roberto Verucchi, Marco Nardi

P29 COHESIVE ENERGY OF MOLECULAR CRYSTALS THROUGH AB INITIO POST-SCF HYBRID METHODS.............................................................................. 88

Lorenzo Maschio, Bartolomeo Civalleri, Kamal Sharkas, Julien Toulouse, Andreas Savin

P30 AB INITIO ANALYTICAL INFRARED AND RAMAN INTENSITIES FOR PERIODIC SYSTEMS THROUGH A CPHF/KS METHOD....................................... 89

Lorenzo Maschio, Bernard Kirtman, Michel Rérat, Roberto Orlando, Roberto Dovesi

P31 COLLECTING AND VALIDATING LDHA CONFORMATIONS FOR AN ENSEMBLE-BASED VIRTUAL SCREENING .......................................................... 90

Rosa Buonfiglio, Maria Ferraro, Federico Falchi, Andrea Cavalli, Matteo Masetti, Maurizio Recanatini

P32 MOLECULAR DYNAMICS OF MACROMOLECULAR SYSTEMS IN LIPID BILAYERS................................................................................................................ 91

Roberta Galeazzi, Luca Massaccesi, Giovanna Mobbili, Michela Pisani


XVI

P33 THE LIPID BILAYER PERMEABILITY OF MOLECULAR SOLUTES: BEYOND THE STANDARD SOLUBILITY-DIFFUSION MODEL.............................................. 92

Giulia Parisio, Alberta Ferrarini

P34 SMOOTH FILLING OF THE SOLVENT-EXCLUDING VOLUME WITH SPHERES ................................................................................................................ 93

Christian Silvio Pomelli

P35 THEORETICAL STUDY OF THE PHOTOIONIZATION CROSS SECTIONS OF METALLOCENES .................................................................................................... 94

P. Decleva, A. Ponzi

P36 THE SOFT X-RAY ABSORPTION SPECTRUM OF THE ALLYL FREE RADICAL.................................................................................................................. 95

M. Alagia, E. Bodo, P. Decleva, S. Falcinelli, A. Ponzi, R. Richter, S. Stranges

P37 BENCHMARKING PERIODIC DISPERSION-CORRECTED DFT CALCULATIONS FOR THE PREDICTION OF MOLECULAR CRYSTAL POLYMORPHISM .................................................................................................... 96


P38 FROM PHENYL CHLORIDES TO α,n-DIDEHYDROTOLUENES (α,n-DHTs) VIA PHENYL CATIONS. A CASSCF INVESTIGATION ........................................... 98

Davide Ravelli, Stefano Protti, Maurizio Fagnoni, Angelo Albini

P39 ELECTRONIC AND EPR SPECTRA OF THE SPECIES INVOLVED IN [W10O32]

4- PHOTOCATALYSIS. A RELATIVISTIC DFT INVESTIGATION............... 99

Davide Ravelli, Daniele Dondi, Maurizio Fagnoni, Angelo Albini, Alessandro Bagno

P40 NITROGEN AND CARBON K-EDGE NEXAFS SPECTRA OF MODEL SYSTEMS FOR C5H5N ON Si(100) : A DFT SIMULATION ................................... 100

M. Romeo, G. Balducci, M. Stener, G. Fronzoni

P41 COARSE-GRAINED MD SIMULATIONS OF THE MESOMORPHIC BEHAVIOUR OF 1-HEXADECYL-3-METHYLIMIDAZOLIUM NITRATE ................ 102

G. Saielli, Y. Ji, R. Shi, G. A. Voth, Y. Wang

P42 RELATIVISTIC DFT CALCULATIONS OF XENON NMR PARAMETERS IN VAN DER WAALS SYSTEMS................................................................................ 103

G. Saielli, A. Bagno

P43 ORBITAL RELAXED DENSITY MATRIX AT LOCAL MP2 LEVEL FOR PERIODIC SYSTEMS: FORMAL ASPECTS AND IMPLEMENTATION ................ 104

Simone Salustro, Lorenzo Maschio


XVII

P44 DEVELOPMENT OF A RELIABLE FORCE FIELD FOR CLASSICAL MD SIMULATIONS IN ALUMINOSILICATES, ENABLING FAST PARALLEL COMPUTATIONS................................................................................................... 105

Andrea Gabrieli, Marco Sant, Pierfranco Demontis, Giuseppe B. Suffritti

P45 A GENERAL ALL-COORDINATES QUANTUM-DYNAMICAL APPROACH FOR DESCRIBING THE VIBRONIC LINESHAPE OF ELECTRONIC CIRCULAR DICHROISM SPECTRA IN EXCITON-COUPLED DIMERS .................................. 106

Fabrizio Santoro

P46 PHOTOPHYSICS & PHOTOCHEMISTRY OF CARBONYL CAROTENOIDS: A COMBINED CASSCF AND TD-DFT STUDY ......................................................... 107

Mireia Segado, Francisco Jose Avila Ferrer, Fabrizio Santoro, Chiara Cappelli, Mariangela Di Donato, Andrea Lapini, Manuela Lima, Roberto Righini

P47 IRON GALL INKS AS 3D COORDINATION POLYMERS A DFT STUDY USING PERIODIC BOUNDARY CONDITIONS.................................................................. 108

Sara Zaccaron, Marco Bortoluzzi, Renzo Ganzerla

P48 INTEGRATED APPROACHES TO NMR SPIN RELAXATION IN FLEXIBLE BIOMOLECULES: APPLICATION TO OLIGOSACCHARIDES.............................. 109

Mirco Zerbetto, Dmytro Kotsyubynskyy, Maria Soltesova, Jozef Kowalewski, Goran Widmalm, Antonino Polimeno

P49 SPECTROSCOPIC PROPERTIES OF THIOPHENE BASED EUROPIUM β-DIKETONATE COMPLEXES: A THEORETICAL STUDY...................................... 110

Ugo Cosentino, Claudio Greco, Giorgio Moro, Luca Bertini, Malgorzata Biczysko, Vincenzo Barone

P50 COMPUTATIONAL SPECTROSCOPY FOR SYSTEMS IN THE CONDENSED PHASE: NICOTINE AS A TEST CASE .................................................................. 112

Franco Egidi, Julien Bloino, Chiara Cappelli, Vincenzo Barone

P51 QUANTUM CHEMISTRY WITHOUT WAVEFUNCTIONS: NEW PROSPECTIVES.................................................................................................... 113

Stefano Conte

P52 PREDICTING THE SPIN-STATE ENERGETICS AND NMR OF IRON COMPLEXES BY DFT .......................................................................................... 114

Andrea Borgogno, Federico Rastrelli, Alessandro Bagno

INDICE DEGLI AUTORI ....................................................................................... 117

LISTA DEI PARTECIPANTI ................................................................................. 121


XVIII

INVITED LECTURES


2


3

TOWARD A MULTIFREQUENCY VIRTUAL SPECTROMETER

Vincenzo Barone

Scuola Normale Superiore, piazza dei Cavalieri 7, 56126 Pisa, Italy

Within the plethora of modern experimental techniques, vibrational, electronic, and resonance spectroscopies are uniquely suitable to probe static and dynamic properties of molecular systems under realistic environmental conditions and in a non-invasive fashion. However, the outcome of spectroscopic studies is rarely interpretable without the support of theoretical treatments providing a link between chemical/electronic structure and spectroscopic properties. Furthermore, the development of more and more sophisticated experimental techniques poses correspondingly stringent requirements on the quality of the models employed to interpret spectroscopic results, and on the accuracy of the underlying chemical-physical descriptions. The predictive and interpretative ability of computational spectroscopy can be clearly demonstrated by state-of-the-art methods available for small molecular systems, which at present yield results comparable to the most accurate experimental measurements. However, the definition of efficient computational approaches aimed at spectroscopic studies of large, complex molecular systems is in general a non-trivial task, and the basic requirement is that such effective models need to reflect a correct physical picture. On these grounds, the present contribution aims to present and analyze several examples illustrating the current status of computational spectroscopy approaches applicable to medium-to-large molecular system in the gas phase and in more complex environments. Particular attention is devoted to theoretical models able to provide data as close as possible to the results directly available from experiment, in order to avoid ambiguities in the interpretation of the latter. The examples range from anharmonic frequencies and IR-Raman intensities of medium size systems, to vibrationally resolved UV-Vis spectra of molecules in solution, to the direct simulation of the ESR spectral line-shapes. The point is also made that computational spectroscopy studies of more complex macro-systems are becoming feasible. Suitable multi-scale approaches aiming at spectroscopic properties of complex molecular systems, of drug design, materials science, nanotechnology, etc. interest, which exploits the new capacities offered by the constant increase in computer performances, will be employed in the development of a research environment for advanced modelling of “soft matter” within the ERC-DREAMS project. [1] Barone, V.; Baiardi, A.; Biczysko, M.; Bloino, J.; Cappelli, C.; Lipparini, F.; Phys. Chem. Chem. Phys. 2012, 14, 12404-12422.


4

DESIGN OF MONO- AND POLYVALENT MIMICS OF

OLIGOSACCHARIDES

Anna Bernardi

Università degli Studi di Milano, Dipartimento di Chimica,

via Golgi 19, 20133Milano, Italy Interference with oligosaccharide-mediated recognition events can be achieved using functional mimics of carbohydrates, that could thus be used to modulate/alter signal transmission, or to prevent the onset of diseases. In recent years our laboratory has designed and prepared glycomimetic ligands of well-known target lectins1 (cholera toxin, DC-SIGN, MBL, PA-IIL). This presentation will focus on our attempts to use standard computational tools for the design of a group of mono- and polyvalent mimics of oligomannosides, directed towards the dendritic cell receptor DC-SIGN.2 Problems deriving from the specific features of carbohydrate-protein interactions will be highlighted and the computational predictions will be compared with experimental data obtained from a variety of biochemical techniques (X-ray, NMR, ITC, SPR, ultracentrifugation). [1]. Bernardi, A.; Cheshev, P. Chemistry Eur. J. 2008, 14, 7434-7441 [2] a) Varga, N.; Sutkeviciute, I.; Guzzi, C.; McGeagh, J.; Petit-Haertlein, I.; Gugliotta, S.;

Weiser, J.; Angulo, J.; Fieschi, F.; Bernardi, A. Chemistry – Eur. J., 2013. accepted; b) Thépaut, M.; Guzzi, C.; Sutkeviciute, I.; Sattin, S.; Ribeiro-Viana, R.; Varga, N.; Chabrol, E.; Rojo, J.; Angulo, J.; Bernardi, A.; Nieto, P.M.; Fieschi, F. J. Am. Chem. Soc. 2013, http://dx.doi.org/10.1021/ja3053305


5

BRIDGING THE GAP BETWEEN THEORY AND EXPERIMENT:

MODELING SOLVENT EFFECTS ON MOLECULAR PROPERTIES

AND SPECTROSCOPIES

Chiara Cappelli

Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa (Italy) & Dipartimento di Chimica e Chimica Industriale, Università di Pisa,

via Risorgimento 35, I-56126 Pisa (Italy) Effective in silico simulation of response and spectroscopic properties of molecular systems in their natural environment is among the most significant tasks of contemporary theoretical and computational chemistry in view of the increasing reliability of the results coupled to the quite straightforward disentanglement of the role of different effects. However, the production of calculated spectroscopic data directly comparable to their experimental counterparts is particularly challenging in the case of solvated systems, that being mainly due to two reasons. First, the extraction of absolute data, especially intensity values, from spectra of solvated systems is far from being trivial, so that raw experimental values are often treated by means of some kind of theoretical assumptions (usually relying on classical theories) in order to extract from them the molecular property. Second, from the purely theoretical and computational point of view, in order to obtain calculated values directly comparable to experiments, the models to be used should reliably represent the experimental sample, i.e., the physical model should be as realistic as possible, which in practice means that all the physical interactions in the sample and between the sample and the probing field have to be taken into account in the model. Among the possible strategies which can be exploited to account for solvent effects on molecular properties and spectroscopies, a relevant role is played by continuum solvation models [1], due to their well-documented accuracy in describing the structure and properties of solvated systems at a low computational cost. An overview of the continuum solvation approach to molecular properties and spectroscopies is given [2], with special emphasis on vibrational spectroscopy. [1] Tomasi, J.; Mennucci, B.; Cammi, R. Chem. Rev. 2005, 105, 2999. [2] Cappelli, C. “Continuum solvation approaches to vibrational properties” in Mennucci,

B.; Cammi, R. Eds. “Continuum Solvation Models in Chemical Physics: from Theory to Application”, Wiley, Chichester, 2007, pp. 167-179.


6

CORRELATED RESPONSE METHODS TO MODEL ABSORPTION,

IONIZATION AND SCATTERING PHENOMENA

Sonia Coriani

Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Trieste, via Licio Giorgieri 1, 34127 Trieste, Italty

An overview of our recent work on the extension of Linear Coupled Cluster Response Theory to compute Near-Edge Absorption Fine Structures [1,2,3], photoionization cross-sections [5] as well as other linear response properties of atoms and molecules in resonant frequency regions [3,4] will be presented. [1] S. Coriani, O. Christiansen, T. Fransson, P. Norman, Phys. Rev. A 2012, 85, 022507. [2] S. Coriani, T. Fransson, O. Christiansen, P. Norman J. Chem. Theory Comp. 2012, 8,

1616. [3] T. Fransson, S. Coriani, O. Christiansen, P. Norman, Submitted to J. Chem. Phys. [4] S. Coriani, J. Kauczor, P. Norman, O. Christiansen, to be submitted. [5] J. Cukras, S. Coriani, P. Decleva, O. Christiansen, P. Norman, to be submitted.


7

GLOBAL OPTIMIZATION METHODS IN CHEMISTRY

Alessandro Fortunelli

CNR-IPCF, via Giuseppe Moruzzi 1, 56124, Pisa, Italy

E-mail: [email protected] A wide variety of systems of chemical interest present a potential energy surface exhibiting a wealth of low-energy local minima, whose number grow exponentially with the system size, separated by appreciable barriers (“rugged potential energy surface”). The predictive description of such systems is a major challenge for theoretical and computational chemistry because of the need of achieving information on global observables (those ultimately determining the system structural response) on the basis of local (limited) information. Searching for the lowest-energy configuration (the global minimum) is the first challenge, and techniques for addressing it are named global optimization (GO) methods. In this talk, recent advances in GO methods will be illustrated, which are based on the combination of random sampling and structural recognition (order parameter) algortithms, their improved efficiency and capabilities, and their application to selected topics. We will focus in particular on the structure and properties of supported metal nanoparticles and nanoalloys1,2,3, ranging from very small clusters via a density-functional basin-hopping (DF-BH) algorithm, their mobility and growth phenomena and the topic of “surface magic clusters”, to large particles via combined density-functional empirical-potential (DF-EP) or empirical-potential global-optimization (EP-GO) searches with the possibility of creating exotic metal-on-oxide phases. Current developments to feasibly reconstruct the topology of local minima and saddle points in the energy hyper-surface so as to extend GO techniques into the dynamic régime will also be discussed in two different directions: (i) a predictive computational methodology in the form of a reactive global minimization (RGO) approach4 to study the catalytic activity of very small (sub-nanometer or ultranano) supported metal clusters, and (ii) to study boundary motion and creep in nanophase materials, showing that reactive configurational search techniques produce correct predictions when compared with accelerated MD methods, thus opening up new avenues of materials science computational design5, 6.


8

[1] R. Ferrando et al. “Interface-stabilized exotic phases of metal-on-oxide nanodots”, ACS Nano 2008, 2, 1849.

[2] G. Barcaro et al. “Patchy Multishell Segregation in Pd-Pt Alloy Nanoparticles”, NanoLett. 2011, 11, 1766.

[3] G. Barcaro et al. “Interface effects on the magnetism of CoPt supported nanostructures”, NanoLett. 2011, 11, 5542.

[4] F. R. Negreiros et al. “A first-principles theoretical approach to heterogenous nanocatalysis”, Nanoscale 2012, 4, 2018.

[5] L. Gragnaniello et al. “Ordered Arrays of Size-Selected Oxide Nanoparticles”, Phys. Rev. Lett. 2012, 108, 195507.

[6] H. Van Swygenhoven, A.Fortunelli, A. Caro, unpublished.


9

THE INTERPLAY BETWEEN ENVIRONMENT AND EXCITED

STATE PROCESSES IN (SUPRA)MOLECULAR SYSTEMS: A

QUANTUM CHEMICAL PICTURE

Benedetta Mennucci

Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via Risorgimento 35, 56126 Pisa, Italy

E-mail: [email protected] Molecular systems in their electronically excited states play a fundamental role in many fields of science. In most cases, their photochemistry and photophysics are strongly affected, if not entirely determined, by the surrounding environment. In addition, when the excited state processes involve a supramolecular structure, a further specificity of the environment is that of influencing the interactions among the molecular subunits. For this reason, a proper integration of models that take into account the effects of the environment into a quantum-mechanical (QM) description is necessary. In this talk, it will be shown that models based on hybrid QM/classical descriptions (either continuum or discrete, or their combination) represent a valid computational strategy but only if mutual polarization effects between the QM and the classical part are possible and all the main physical specificities of the environment are properly taken into account [1]. Examples of applications of these methods to different molecular and supramolecular phenomena (absorption, emission and energy transfer) in the presence of environments of increasing complexity will be presented and discussed. [1] B. Mennucci, Phys. Chem. Chem. Phys., 2013, DOI: 10.1039/C3CP44417A


10

THEORETICAL STUDIES OF C-BASED NANOSTRUCTURES

Rocco Martinazzo, Matteo Bonfanti, Simone Casolo, Gian Franco Tantardini

Università degli Studi di Milano, Dipartimento di Chimica Graphene isolation in 2004 by the Machenster group initiated an explosion of scientific activity which promises to change our everyday life. Thanks to its extraordinary electronic, optical and mechanical properties it is an ideal candidate for ultrafast electronic and optical devices, flexible electronic, functional lightweight components and advanced batteries. Being one-atom thick – it is indeed the first truly two-dimensional material ever produced – it is extremely sensitive to the presence of adsorbed atoms and molecules and, more generally, to defects such as vacancies, holes and/or substitutional dopants. This property, apart from being useful for molecular sensor devices, can also be employed to tune graphene electronic properties. Here, we briefly review the basic features of atomic-scale defects that can be useful for material design, and the chemistry behind them [1-4]. The focus will be on the so-called pz vacancies, i.e. those defects which cause the disappearance of a carbon pz orbital from the π-π* band systems, either because of a strong (chemical) bond with a lattice atom or because of the removal of a carbon atom. The contribution will thus cover the issues of clustering of adatoms, their magnetic behavior, analogies and differences with carbon atom vacancies and their debated magnetic properties, the possibility of nano-structuring the substrate to tailor specific properties, and the role of edges in the adsorption process. We will also touch a few dynamical issues, e.g. the role of the above defects in limiting graphene electronic transport properties, and the reactivity of H atoms to form H2 molecules. [1] M. Bonfanti, S. Casolo, G. F. Tantardini, A. Ponti and R. Martinazzo, “A few simple

rules governing hydrogenation of graphene dots”, J. Chem. Phys. 2011, 135, 164701. [2] R. Martinazzo, S. Casolo and G.F. Tantardini, “The effect of atomic-scale defects and

dopants on graphene electronic structure”, in: Physics and applications of Graphene – Theory, Editor: S. Mikhailov, Intech (2011).

[3] S. Casolo, R. Martinazzo and G.F. Tantardini, “Band Engineering in Graphene with Superlattices of Substitutional Defects”, J. Phys. Chem. C 2011, 115, 3250.

[4] R. Martinazzo, S. Casolo and G. F. Tantardini, “Symmetry-induced band-gap opening in graphene superlattices”, Phys. Rev. B 2010, 81, 245420.


11

COMPUTATIONAL SIMULATIONS OF SOLID STATE NMR

SPECTRA: A NEW ERA IN STRUCTURE DETERMINATION OF

OXIDE GLASSES

Thibault Charpentier,1 Maria Cristina Menziani2, Alfonso Pedone2

(1) CEA, IRAMIS, SIS2M, CEA-CNRS UMR 3299, 91191 Gif-sur-Yvette cedex (France) (2) Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Modena e

Reggio Emilia, Via G. Campi 183, 41125 Modena (Italy) In this communication a computational approach which couples molecular dynamics and DFT simulations for the calculation of NMR parameters, line widths and shapes of the spectra of oxide glasses will be presented.1,2 Emphasis is given to the decisive role of this approach both as interpretative tool for a deeper understanding of the spectral behavior of complex systems and as predictive instrument to map NMR data into a distribution of structural parameters and backwards. This approach will be applied to ‘simple’ network former glasses and more complex silicates, aluminosilicate, phosphosilicate and borosilicate glasses of scientific relevance.3-6 [1] Pedone, A.; Charpentier, T.; Menziani, M. C. Phys. Chem. Chem. Phys. 2010, 12, 6054. [2] Charpentier, T.; Kroll, P.; Mauri, F. J. Phys. Chem. C 2009, 113, 7917. [3] Pedone, A.; Charpentier, T.; Malavasi, G.; Menziani, M. C. Chem. Mater. 2010, 22, 5644. [4] Pedone, A.; Charpentier, T.; Menziani, M. C. J. Mater. Chem. 2012, 22, 12599. [5] Pedone, A.; Gambuzzi, E.; Malavasi, G.; Menziani, M. C. Theor. Chem. Acc. 2012 131,

1147. [6] Pedone, A.; Gambuzzi, E.; Menziani, M. C. J. Phys. Chem. C 2012, 115, 14599.


12

COMPUTATIONAL STUDIES ON THE hERG POTASSIUM CHANNEL

Maurizio Recanatini, Matteo Masetti

Department of Pharmacy and Biotechnology, University of Bologna, Via Belmeloro 6, I-40126, Bologna.

The voltage-gated hERG potassium channel (Kv 11.1) is expressed in several organs and tissues, and in the heart, it is responsible for the rapid component of the delayed K+ current (Ikr), which plays a fundamental role in the repolarization phase of the cardiac action potential [1]. Alterations in the hERG functionality have been associated to a potentially lethal proarrhythmic condition known as long QT syndrome-type 2 (LQTS2) [2]. The hERG dysfunction caused by an accidental block by drugs is of pivotal importance in the pharmaceutical research area since, although rare in occurrence, its seriousness has raised severe concerns about drug safety [3]. In this scenario, assessing the blockade activity at the early stages of a drug discovery process, as well as the possibility to develop drugs specifically designed to contrast the block, is highly desirable [4]. On the other hand, the occurrence of inherited LQTS2 forms has been related to the expression of functionally assembling albeit non-conductive mutants. From this perspective, investigating the ion conduction at an atomistic detail opens promising possibilities to understand the mechanisms leading to altered channel functionality. From a computational point of view, dealing with the hERG channel poses several issues that must be addressed with diverse and specific techniques, ranging from well established quantitative structure-activity relationship methods to the most advanced biophysical simulations. In this presentation, several aspects of the hERG modeling will be covered, with a special emphasis on the identification of new molecules able to modulate the channel functionality. [1] Tseng, G.-N. J. Mol. Cell. Cardiol. 2001, 33, 835−849. [2] Sanguinetti, M. C.; Tristani-Firouzi, M. Nature 2006, 440, 463−469. [3] Recanatini, M.; Poluzzi, E.; Masetti, M.; Cavalli, A.; De Ponti, F. Med. Res. Rev. 2005,

25, 133−166. [4] Xu, X.; Recanatini, M.; Roberti, M.; Tseng, G.-N. Mol. Pharmacol. 2008, 73,

1709−1721.


13

CHARGE DISPLACEMENT ANALYSIS: A DIFFERENT VIEW OF

BONDING, FROM NON-COVALENT INTERACTIONS TO

COORDINATION CHEMISTRY

Francesco Tarantelli

Dipartimento di Chimica, Università di Perugia, e ISTM-CNR

Assessing reliably the presence, extent, and effects of charge transfer (CT) is notoriously a controversial, elusive goal in several areas of chemistry. And yet CT is a long-standing, ubiquitous staple of chemical reasoning, useful to interpret and model many experimental observations and features of chemical interactions. We review here a simple theoretical approach, based on the so-called charge-displacement curves [1], which has proved to be helpful to ascertain and measure the extent of CT taking place when two species interact. This is especially useful for non-covalent interactions such as hydrogen bonding where, for example, we have conclusively established that an experimentally detectable, strongly anisotropic, CT characterizes even weakly bound water binary complexes [2] (where water may act as donor or acceptor depending on orientation) but not other similar hydride adducts. By careful comparison with the experiments, we have been able to estimate the stabilization energy associated with CT at 2-3 meV per millielectron transferred, a rate which we find remarkably constant across a range of systems. A simple physical model for the kinetic energy loss accompanying electron delocalization helps to rationalize these findings [3]. Similarly useful results have been obtained clarifying the role of CT in halogen bonding. Among other successful fields of application of the CD analysis is coordination chemistry, where the popular Dewar-Chatt-Duncanson model of the bonding, in terms of donation and back-donation components, can be put for the first time on a firm quantitative basis [4]. This has been instrumental, for example, for elucidating some aspects of gold(I) coordination chemistry, a gold mine ;-) of modern catalysis but still little understood, and in particular the key role played by back-donation, previously widely believed to be marginal. The forward and backward CT components have also been put in quantitative relation with experimental observables such as ligand IR frequency and geometric distortion, opening the way for useful interpretative models.

[1] L. Belpassi, I. Infante, F. Tarantelli, L. Visscher, J. Am. Chem. Soc. 2008, 130, 1048-1060.

[2] L. Belpassi, M.L. Reca, F. Tarantelli, L.F. Roncaratti, F. Pirani, D. Cappelletti, A. Faure, Y. Scribano, J. Am. Chem. Soc. 2010, 132, 13046-13058.

[3] D. Cappelletti, E. Ronca, L. Belpassi, F. Tarantelli, F. Pirani, Acc. Chem. Res. 2012, 45, 1571-1580.

[4] N. Salvi, L. Belpassi, F. Tarantelli, Chem. Eur. J. 2010, 16, 7231-7240.


14

CATALYTIC GENERATION OF HYDROGEN ASSISTED BY

METAL-BASED HOMOGENEOUS CATALYSTS:

COMPUTATIONAL INSIGHTS

Emilia Sicilia, Valeria Butera, Nino Russo

Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Ponte P. Bucci

Cubo 14c, 87030 Arcavacata di Rende (Italy), [email protected] Interest in sustainable non-hydrocarbon-based fuels for transportation has grown as the recognition that the supply of fossil fuels is limited and the deleterious environmental effects of burning them has come into public focus. The use of hydrogen (H2) has been proposed as an alternative, but its use in pure form is undesirable due to the high pressures or low temperatures required to store useful quantities. Currently, there are three leading alternative methodologies to store H2: sorbents (nanoporous materials), metal hydrides, and so-called chemical hydrides. We have concentrated our efforts [1,2] on the investigation of the mechanistic aspects of the processes for the release of H2 from chemical hydrides assisted by homogeneous metal-based catalysts. Here, the outcomes of our computational analysis of some reactions for the catalytic generation of hydrogen from potential hydrogen storage materials, such as amine-boranes, will be presented. All the presented results show how the intervention of theoretical investigation is essential to disentangle the mechanistic details experimentally envisaged and to provide precious hints for the improvement of existing catalysts [1] Chowdhury, S.; Himo, F.; Russo, N.; Sicilia, E. J. Am. Chem. Soc. 2010 132, 4178-4190. [2] Butera, V.; Russo, N.; Sicilia, E. Chem. Eur. J. 2011 17, 14586-14592.


15

STRUCTURE AND REACTIVITY OF METAL-SUPPORTED

SELF-ASSEMBLED MOLECULAR LAYERS

FROM FIRST PRINCIPLES

Andrea Vittadini†

CNR-ISTM, DiSC, and CR-INSTM “Village”, via Marzolo 1, 35131, Padova. The autonomous ordering and assembly of molecules on well-defined solid surfaces represent a promising route to the fabrication of functional molecular devices of nanometer size [1]. To this end, achieving a good and reproducible control over the composition and the structure of molecular layers is obviously mandatory. Precious indications in this respect can be provided by accurate investigations where surface science experiments (such as scanning tunnelling microscopy) and theoretical calculations are carried out synergistically. In this talk, I will discuss the results obtained by applying this approach to the case of iron phthalocyanine layers supported on Ag(110). In particular, I will show that the adsorbate-support coupling can be suitably steered acting on the coverage. This in turn allows to take control of the oxygen reduction reaction—a key process in energy conversion and storage. [1] Barth, J. V.; Costantini, G.; Kern, K. Nature 2005, 437, 671-679. †In collaboration with, V. Barone, M. Casarin, A. Cossaro, M. Di Marino, D. Forrer, L. Floreano, M. Pavone, M. Sambi, F. Sedona, E. Tondello.


16


17

COMUNICAZIONI ORALI


18


19

SELF-CONSISTENT CONTINUUM SOLVATION (SCCS) IN PERIO DIC

ELECTRONIC-STRUCTURE CALCULATIONS

Oliviero Andreussi,a,b Nicola Marzarib

a Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Italy b Theory and Simulations of Materials (THEOS), École Polytechnique Fédérale de Lausanne,

Switzerland The solvation model proposed by Fattebert and Gygi [1] and Scherlis et al. [2] is reformulated [3], overcoming some of the numerical limitations encountered and extending its range of applicability. The resulting self-consistent continuum solvation (SCCS) model has been implemented in the public-domain PWSCF package of the Quantum-ESPRESSO distribution [4] (an open-source massively parallel environment for electronic-structure simulations, based on density-functional theory and beyond, periodic-boundary conditions, plane-wave basis sets, and pseudo-potentials to represent ion-electron interactions). The SCCS model provides a very effective and compact fit of computational and experimental data, whereby the static dielectric constant of the solvent and one parameter allow to fit the electrostatic energy provided by the PCM model with a mean absolute error of 0.3 kcal/mol on a set of 240 neutral solutes. Two parameters allow to fit experimental solvation energies on the same set with a mean absolute error of 1.3 kcal/mol. A detailed analysis of these results, broken down along different classes of chemical compounds, shows that several classes of organic compounds display very high accuracy, with solvation energies in error of 0.3-0.4 kcal/mol, whereby larger discrepancies are mostly limited to self-dissociating species and strong hydrogen-bond forming compounds. When applied to the study of charged solutes, the SCCS model shows remarkable results for positive ions, with solvation energies of organic cations in error of 2.2 kcal/mol, whereby larger discrepancies are found for negative ions, with errors in the same range of other computational tools (~4-5 kcal/mol). [1] Fattebert, J. L.; Gygi, F. J. Comput. Chem. 2002, 23, 662. [2] Scherlis, D.; Fattebert, J. L.; Gygi, F.; Cococcioni, M.; Marzari, N. J. Chem. Phys. 2006,

124, 074103. [3] Andreussi, O.; Dabo, I.; Marzari, N.; J. Chem. Phys. 2012, 136, 064102. [4] Giannozzi, P. ; et al. J. Phys.: Condens. Matter 2009, 21, 395502.


20

AN INVESTIGATION OF THE PHOTOPHYSICAL PROPERTIES OF

MINOR GROOVE BOUND AND INTERCALATED MOLECULAR

PROBES FOR NUCLEIC ACIDS, THROUGH QM AND

SPECTROSCOPIC TOOLS

Alessandro Biancardi, Tarita Biver, Benedetta Mennucci

Dipartimento di Chimica e Chimica Industriale, via Risorgimento 35, 56126 – Pisa E-mail: [email protected]

The fluorescence of molecular probes for nucleic acids is well known to show complex changes due to both intercalation and minor groove binding [1, 2]. To investigate this behavior, quantum-mechanical calculations using time-dependent density functional theory (TDDFT), coupled with polarizable continuum and/or atomistic models, were performed [3, 4, 5] in combination with spectroscopic measurements of the probe in the different environments, ranging from a homogeneous solution to the minor groove or intercalation pockets of double stranded nucleic acids. The overall data collected provided information on the features of the “light-switch” by fluorescent probes and the comparison between experimental and calculated photophysical properties allowed to explain and rationalize both shifts and quenching/enhancing effects on fluorescence due to solvation, dimerization, intercalation and minor groove binding. [1] Neidle, S; Nature Chemistry 2012, 4, 594. [2] Pichon, A; Nature Chemistry 2012, 4, 593. [3] Biancardi, A.; Biver, T.; Marini, A.; Mennucci, B.; Secco, F. Phys. Chem. Chem. Phys.

2011, 13, 12595. [4] Biancardi, A.; Biver, T.; Mennucci, B.; Secco, F. Phys. Chem. Chem. Phys. 2013

(accepted, DOI: 10.1039/C3CP44058C). [5] Biancardi, A.; Biver, T.; Barone, G.; Mennucci, B.; Secco, F. (in preparation).


21

THE STRUCTURE OF IONIC LIQUIDS FROM A MOLECULAR

PERSPECTIVE: RECENT THEORETICAL

AND EXPERIMENTAL RESULTS

E. Bodo, R. Caminiti

Dept. of Chemistry, University of Rome “La Sapienza”, Italy

E-mail: [email protected] Among the most exciting and successful materials developed and studied in the last twenty years, ionic liquids [1] are among those that can certainly claim one of the most rich field of applications in industry and in applied technological research. We have recently analyzed the behavior of such compounds by using a

variety of theoretical approaches including: ab-initio gas phase cluster optimizations, molecular dynamics simulations of the bulk phases and ab-initio first principle molecular dynamics. The collaboration with experimental groups allows the validation of our results with precise measurements such as X-ray and Neutron structures, Raman and NEXAFS spectra. We shall report some of the most recent results obtained in our group [2,3] focusing in particular on the studies of protic ionic liquids and their complex liquid structure due to hydrogen bonding features.

[1] Rogers, R. D., Plechkova, N. V., Seddon, K. R., Eds. “Ionic Liquids: From Knowledge to

Application”; ACS Symp. Ser.; 2009; Vol. 1030; Plechkova, N. V.; Seddon, K. R., Chem. Soc. Rev. 2008, 37, 123–150.

[2] E. Bodo, R. Caminiti, J. Chem. Phys. A 2010, 114, 12506; E. Bodo, M. Chiricotto and R. Caminiti, J. Phys. Chem. B 2011, 115, 14341-14347.

[3] E. Bodo, P. Postorino, S. Mangialardo, G. Piacente, F. Ramondo, F. Bosi, P. Ballirano, and R. Caminiti, J. Phys. Chem. B 2011, 115 13149-13161. L. Gontrani ,E. Bodo, A. Triolo, F. Leonelli, P. D’Angelo, V. Migliorati, R. Caminiti., J. Phys. Chem. B 2012, 116, 13024-13032.


22

DFTB/PCM AND TD-DFTB/PCM APPROACHES FOR CALCULATION

OF SPECTROSCOPICAL PROPERTIES OF LARGE SYSTEMS

IN SOLUTION

Carnimeo I.,a,b Scalmani G.,c Barone V.d,b

a Universita’ degli Studi di Pisa, Dipartimento di Chimica e Chimica Industriale, Via Risorgimento, 35 – 56126 – Pisa, Italia

b INFN, Sezione di Pisa c Gaussian, Inc., 340 Quinnipiac Street Building 40,

Wallingford, Connecticut 06492, United States d Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126, Pisa

A new computational approach, has been recently proposed for the modellization of large systems in solution [1]. DFTB method has been integrated with the Polarizable Continuum Solvent Model, in order to take into account the polarization effects induced by the bulk of the solvent on the spectroscopical properties of the solute. The implementation of the ground state first and second derivatives allows geometry optimizations and harmonic frequency calculations in different solvents. The PCM contribution to the gas phase TD-DFTB [2] response matrices has been also implemented, in order to compute the solvatochromic shifts of the excited state properties. The new approach has been first tested on several organic molecules, in order to provide a general overview of the performances, also in comparison with other solvation models proposed for the DFTB method [3-5]. Then, vibrational frequencies and excitation energies have been computed for Uracil and Red Nile in solution, and a good agreement with results obtained using more accurate metods has been found. [1] Barone V., Carnimeo I., Scalmani G., JCTC, 2012 (just accepted). [2] Trani F., Scalmani G., Zheng G., Carnimeo I., Frisch M. J., Barone V., JCTC 2011, 7,

3304. [3] Lu, Z.; Liu, H.; Elstner, M.; Yang, W., Reviews of modern quantum chemistry: a

celebration of the contribution of Robert G. Parr, 2002, 1606. [4] Hou, G.; Zhu, X.; Cui, Q., JCTC 2010, 6, 2303. [5] Xie, L.; Liu, H., J. Comp. Chem. 2002, 23, 1404.


23

PROTEIN FIELD EFFECT ON THE DARK STATE OF

11-CIS RETINAL IN RHODOPSIN BY QUANTUM MONTE

CARLO/MOLECULAR MECHANICS

Emanuele Coccia,a Daniele Varsanob , Leonardo Guidonia

a Dipartimento di Scienze Fisiche e Chimiche, Università degli Studi dell’Aquila, via Vetoio, 67100, L’Aquila, Italy

b Dipartimento di Fisica, “Sapienza” – Università di Roma, piazzale Aldo Moro 5, 00185, Rome, Italy

The accurate determination of the geometrical details of the dark state of 11-cis Retinal in Rhodopsin represents a fundamental step for the rationalization of the protein role in the optical spectral tuning in the vision mechanism [1]. We have calculated high-level geometries in gas phase and in protein environment using the correlated Variational Monte Carlo method [2-5]. The Bond Length Alternation of the conjugated carbon chain of the chromophore in gas phase shows a significant reduction when moving from the ß-ionone ring to the nitrogen whereas, as expected, the protein environment reduces the electronic conjugation. The proposed dark state structure is fully compatible with solid-state NMR data reported by Carravetta et. al. [J. Am. Chem. Soc. 2004, 126, 3948-3953]. TDDFT/B3LYP calculations on such geometries show a blue opsin shift of 0.28 and 0.24 eV induced by the protein for S1 and S2 states, consistently with literature spectroscopic data. The effect of the geometrical distortion alone is a red shift of 0.21 and 0.16 eV with respect to the optimized gas phase chromophore [5]. [1] Palczewski, K. Annuv. Rev. Biochem. 2006, 75, 743-767. [2] Foulkes, W. M. C.; Mitas, L.; Needs, R. J.; Rajagopal, G. Rev. Mod. Phys. 2001, 73, 33-

83. [3] Casula, M.; Attaccalite, C.; Sorella, S. J. Chem. Phys. 2004, 121, 7110-7126. [4] Coccia, E.; Guidoni, L. J. Comput. Chem. 2012, 33, 2332-2339. [5] Coccia, E.; Varsano, D.; Guidoni, L. J. Chem. Theor. Comput., doi:10.1021/ct3007502.


24

COULOMB STURMIAN ORBITALS AND HYPERSPHERICAL

HARMONICS AS BUILDING-BLOCKS FOR QUANTUM CHEMICAL

APPLICATIONS

Cecilia Coletti,a Danilo Calderini,b Vincenzo Aquilantic

a Dipartimento di Farmacia, Università G. d’Annunzio Chieti-Pescara, Via dei Vestini, 66100 Chieti

b Scuola Normale Superiore di Pisa, Via Consoli del Mare, 2, 56126 Pisa c Dipartimento di Chimica, Università di Perugia, Via Elce di Sotto 8, 06100 Perugia

In the last years, Sturmian orbitals are emerging as an interesting alternative to Slater-type and Gaussian-type orbitals to solve quantum chemistry problems [1,2]. One of their main strengths lies in the complete reciprocity between these basis sets in configuration space and their counterparts in momentum space, hyperspherical harmonics. Because the superposition integrals between these functions can be written as elements of angular momentum algebra and its generalizations [3], they can also be used to connect alternative Sturmian bases, arising from the separation of the hydrogenic Schrödinger equation in different sets of coordinates [4]. This provides a most powerful tool to be exploited for building up the most appropriate basis sets to solve multielectron and/or multicenter problems. Moreover, this approach is completely general and can be extended to any dimension, allowing, for instance, the use of alternative basis sets to deal with the d-dimensional hydrogen atom, though the usual tridimensional Sturmians (and the corresponding O(4) hyperspherical harmonics) are most commonly employed in applications. The quantum mechanics of atoms and molecules can be discussed in terms of the breaking of the hyperspherical symmetry of a d-dimensional hydrogenoid atom, d=3(N-1) for N body Coulomb problems, due to the introduction of further charged particles (electrons and/or nuclei). Thus, in configuration space, Sturmian basis functions can be used as expansion basis sets to build up atomic and molecular orbitals. Additionally, one can choose among alternative hyperspherical harmonics pertaining to different subgroup chain reductions of the original (d+1)-dimensional rotation group and thus possessing different symmetry properties [5]. [1] Avery, J.; Avery, J. Generalized Sturmians and Atomic Spectra. 2006, World Scientific,

Singapore. [2] Calderini, D.; Cavalli, S.; Coletti, C.; Grossi, G.; Aquilanti, V. J. Chem. Sci, 2012, 124,

187. [3] Aquilanti, V.; Caligiana, A.; Cavalli, S.; Coletti, C. Int. J. Quantum Chem, 2003, 92, 212. [4] Aquilanti, V., Cavalli, S., Coletti, C. Chem. Phys. Lett., 2001, 344, 587. [5] Aquilanti, V.; Cavalli, S.; Coletti, C.; Di Domenico, D.; Grossi, G. Int Rev Phys Chem,

2001, 40, 673.


25

SELECTIVE HYDROGENATION OF 2-METHYL-3-BUTYN-2-OL

ON Pd CATALYSTS

Remedios Cortese, Francesco Ferrante, Antonio Prestianni, Dario Duca

Dipartimento di Fisica e Chimica dell’Università, viale delle Scienze Ed. 17, I-90128 Palermo

In the frame of the heterogeneous catalysis, it is well known that size and shape effects play a primal role in driving activity and selectivity [1] and sometimes in giving structure-sensitive reactions [2]. Recently, Crespo-Quesada et al. [3] reported that the 2-methyl-3-butyn-2-ol (MBY) selective reduction on palladium is strongly influenced both by the metal planes – namely, {100} and {111} – and by the reaction site topologies involved in the hydrogenation while the adsorption energies drove the catalytic kinetics. In fact, triple to double-bond reduction seemed to occur four times faster on surface sites with respect to edge or corner sites. Conversely, double to single-bond reduction seemed to occur almost exclusively on edge sites. Moreover, {100} and {111} planes would seem to be more active in the triple-bond and double-bond hydrogenation, respectively. In order to understand and, hopefully, drive these structure-sensitive effects Density Functional Theory (DFT) calculations were performed. A Pd30 cluster was employed as the model for the catalyst. This was cut from a fcc palladium fragment, to obtain both (100) and (111) faces (see Figure 1). Different sites and binding modes were considered to describe either the MBY or 2-methyl-3-buten-2-ol (MBE) interaction and hydrogenation, occurring on the palladium surface. Kinetic studies on MBY and MBE hydrogenation over the Pd30 cluster showed very close activation energy values, irrespective of the surface species considered. On the contrary, the MBY and MBE adsorption energies on the different sites of the palladium faces and the corresponding structural changes were peculiar to the different adsorbed species and plane sites and could be easily connected to the activation of the unsaturated bonds hence to the reactivity of the differently adsorbed species. These results, finally, confirmed the already claimed structure sensitivity of the title reaction and, moreover, the higher reactivity of MBY with respect of MBE, which was also observed [3]. [1] Duca, D.; Barone, G.; Varga, Zs. Catal. Letters, 2001, 72 (1-2), 17–23. [2] Bond, G. C. Metal-Catalysed Reaction of Hydrocarbons, Springer NY, 2005. [3] Crespo-Quesada, M.; Yarulin, A.; Jin, M.; Younan, X.; Kiwi-Minsker, L. J. Am. Chem.

Soc., 2011, 133 (32),12787–12794.

Figure 1. Pd30 cluster, showing both the (100) and (111) faces


26

IDENTIFICATION AND CHARACTERIZATION OF NEW DNA

G----QUADRUPLEX BINDERS SELECTED BY A COMBINATION OF

LIGAND AND STRUCTURE-BASED VIRTUAL SCREENING

APPROACHES

Costa G.,a Alcaro S.,a Musetti C.,b Distinto S.,c Casatti M.,b Zagotto G.,b Artese A.,a Parrotta L.,a Moraca F.,a Ortuso F.,a Maccioni E.,c Sissi C.b

a Dipartimento di Scienze della Salute, Università di Catanzaro, Campus “Salvatore Venuta”, Viale Europa, 88100 Catanzaro, Italy

b Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via Marzolo 5, 35131, Padova, Italy

c Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy

G-quadruplex structures are nucleic acid arrangements assumed by guanine-rich sequences and stabilized by the planar pairing of four guanines through eight Hoogsteen hydrogen bonds. These sequences are found in crucial positions of the genome, such as at telomeric ends, ribosomal DNA (rDNA), RNA, or gene promoter regions (for example, c-myc, bcl-2, or c-kit) [1]. Nowadays, it has been demonstrated that DNA G-quadruplex arrangements are involved in cellular aging and cancer, thus boosting the discovery of selective binders for these DNA secondary structures. By taking advantage of available structural and biological information on these structures, we performed a high throughput in silico screening of commercially available molecules databases by merging ligand- and structure-based approaches by means of docking experiments.

Figure 1: Virtual screening workflow.

Compounds selected by the virtual screening procedure were then tested for their ability to interact with the human telomeric G-quadruplex folding by circular dichroism, fluorescence spectroscopy, and photodynamic techniques. Interestingly, our screening succeeded in retrieving a new promising scaffold for G-quadruplex binders characterized by a psoralen moiety.


27

[1] Huppert, J. L. Biochimie 2008, 90, 1140-1148.


28

AB INITIO SIMULATION AS THE KEY TOOL TO INTERPRET THE

IR REFLECTANCE SPECTRA OF CRYSTALLINE SOLIDS

M. De La Pierre,a C. Carteret,b R. Dovesia

a Dipartimento di Chimica, Università degli Studi di Torino, Italy b Laboratoire de Chimie Physique et Microbiologie pour l’Environnement,

Université de Lorraine, France Quantum-mechanical simulation by means of hybrid HF-DFT functionals has demonstrated very high accuracy in the prediction of IR frequencies and intensities of crystalline solids [1,2]. Such an achievement nowadays represents the starting point for the advanced application of simulation in the characterization of the IR reflectance spectra. These spectra contain a high amount of information, which is accessible through the relations among reflectance spectrum, dielectric function and frequencies/intensities of the vibrational modes. The extraction of these data from the spectra requires a delicate best-fit process involving a large number of parameters. Simulation here plays a crucial role, providing the full set of fundamental modes with accurate frequencies and intensities, which is the ideal starting guess for the best-fit. Low intensity fundamentals are identified, whereas peaks not corresponding to fundamental computed modes are recognized as combinations or overtones. Overall, a straightforward scheme can be built, that permits the interpretation of almost all the spectral features of the spectra. Examples are discussed [3,4] to illustrate the effectiveness of the synergy between simulation and experiments. [1] R. Dovesi, M. De La Pierre, A.M. Ferrari, F. Pascale, L. Maschio, C. M. Zicovich-

Wilson, Am. Miner. 2011, 96, 1787. [2] R. Demichelis, H. Suto, Y. Noël, H. Sogawa, T. Naoi, C. Koike, H. Chihara, N.

Shimobayashi, M. Ferrabone, R. Dovesi, Mon. Not. R. Astron. Soc. 2012, 420, 147. [3] C. Carteret, M. De La Pierre, M. Dossot, F. Pascale, A. Erba, R. Dovesi, J. Chem. Phys.

2013, 138, 014201. [4] M. De La Pierre, C. Carteret, R. Orlando, R. Dovesi, submitted to J. Comput. Chem.


29

AB INITIO TEMPERATURE EFFECT ON ONE-ELECTRON

PROPERTIES OF SOLIDS

Alessandro Erba,* Cesare Pisani, Matteo Ferrabone, Roberto Dovesi

Dipartimento di Chimica, Università di Torino, via Giuria 5 10125, Torino, Italy * E-mail: [email protected]

Quite recently, the entrance into a new age of molecular quantum chemistry has been declared: “In the fourth age we are able to incorporate into our quantum chemical treatment the motion of nuclei [...] and compute accurate, temperature-dependent, effective properties, thus closing the gap between measurements and electronic structure computations” [1]. Nowadays, a variety of solid state ab initio quantum chemical methods is available for the study of many properties of the ground state of crystals at zero temperature. In this contribution, we present and discuss two schemes: (i) a fully ab initio technique for the determination of atomic anisotropic displacement parameters (ADP) of crystalline materials within the harmonic approximation to the lattice potential [2]; (ii) a harmonic Monte Carlo ab initio approach for the description of nuclear motion effects on the electronic density matrix of crystalline materials [3]: in the frame of the Born-Oppenheimer approximation, nuclear motions in crystals can be simulated rather accurately using a harmonic model. In turn, the electronic first-order density matrix can be expressed as the statistically weighted average over all its determinations each resulting from an instantaneous nuclear configuration. Such schemes have been developed within the formalism of all-electron atom-centered basis sets, one-electron Hamiltonians (Hartree-Fock, Density-functional-theory, hybrids) and periodic boundary conditions, and implemented in the CRYSTAL program for solid state quantum chemistry. [1] A. G. Császár, C. Fábri, T. Szidarovszky, E. Mátyus, T. Furtenbacher, and G. Czakó,

Phys. Chem. Chem. Phys. 2012, 14, 1085. [2] A. Erba, M. Ferrabone, R. Orlando and R. Dovesi, J. Comput. Chem. 2013, 34, 346. [3] C. Pisani, A. Erba, M. Ferrabone and R. Dovesi, J. Chem. Phys. 2012, 137, 044114.


30

MODIFIED ION PAIR INTERACTION FOR WATER DIMERS ON

SUPPORTED MgO ULTRATHIN FILMS

Anna Maria Ferrari,a Livia Giordanob

aDipartimento di Chimica IFM, Università di Torino and NIS –Nanostructured Interfaces and Surfaces – Centre of Excellence. V. P. Giuria 7, 10125 Torino, Italy

b Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Cozzi 53, 20125 Milano, Italy

The dissociation of water dimers at MgO(100) surface and MgO ultra-thin films on Ag(100) has been studied by means of pure DFT and hybrid functionals calculations. We demonstrate that at the intermediate regime between the isolated molecule and the water monolayer, barrierless dissociation of water occurs when assisted by another water molecule. The metal support had been showed to crucially influence the overall process. Indeed, on the metal supported ultrathin film, the dissociated form is noticeably stabilized, at variance with the MgO(100) surface, where the dissociated fragments can easily recombine. The stabilization of the dissociated charged fragments arises from the polarization of the electron density at the oxide-metal interface and by the polaronic distortion of the oxide film. The presence of the metallic substrate strongly weakens the interaction after the dissociation, by changing the nature of the newly formed ion pair, with possible consequence of the dynamics and the reactivity of water fragments on the oxide ultra-thin film.


31

THE PHASE DIAGRAM OF HARD HELICES:

CLASSICAL DFT AND MONTE CARLO SIMULATIONS

Elisa Frezza,a Alberta Ferrarini,a Hima Bindu Kolli,b Achille Giacometti,b Giorgio Cinacchic

aDipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy

bDipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari di Venezia, Dorsoduro 2137, 30123 Venezia, Italy

cDepartamento de Física Téorica de la Materia Condensada, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain

Since the early Onsager work [1], there have been several demonstrations that purely hard-core repulsions are sufficient for the formation of ordered phases. Recent investigations have revealed the unexpected complexity of the ordered structures obtained by changing the shape of hard particles [2]. The helix is a typical structural motif in nature: for example, polynucleotides, proteins and collagen fibres are all right-handed helices [3]. Rigid and semiflexible helical polymers can exhibit ordered phases, whose features are only partially understood. We have investigated the phase diagram in systems of hard helical particles, using classical DFT and Monte Carlo computer simulations. Motivation of this work resides in the ubiquity of the helical shape motif in many natural and synthetic polymers, as well as in the well known importance that the details of size and shape have in determining the phase behaviour and properties of soft condensed matter systems. We discuss the differences with the corresponding spherocylinder phase diagram [4] and find that the helix parameters affect the phase behaviour and the existence of the nematic phase. We find that at high helicities Onsager theory significantly departs from numerical simulations even when improvements are included to account for the non-convexity of particles. The discrepancies increase with increasing density and upon going from the isotropic to the ordered phases. The unexplored compact structure realm occurring for such non-convex objects at high densities and pressures will also be briefly discussed.

[1] Onsager, L. Ann. N.Y. Acad. Sci.1949, 51, 627–659. [2] Damasceno, P.; Engel, M.; Glotzer, S.C. Science 2012, 337, 453–457. [3] Hamley, I. Soft Matter 2010, 6, 1863-1871. [4] Bolhuis, P.; Frenkel, D. J. Chem. Phys. 1996, 106, 666-687.


32

SILICATE AND ALUMINOSILICATE GLASSES: PROBING

NETWORK ARRANGEMENT BY SOLID STATE NMR

SPECTROSCOPY AND ACCURATE FIRST PRINCIPLE

CALCULATIONS

Elisa Gambuzzi,a Alfonso Pedonea, Maria Cristina Menziani,a

Thibault Charpentierb

a Università degli Studi di Modena e Reggio Emilia, Dip. di Scienze Chimiche e Geologiche, via G. Campi 183, 41125 Modena, Italia

b Commissariat à l’Energie Atomique, IRAMIS / SIS2M / LSDRM, CEA Saclay SIS2M, Bât 125, F-91191 Gif-sur-Yvette cedex, FRANCE

Silicate and aluminosilicate glasses play an important role in nuclear waste confinement and are the ideal reference systems to study geological processes. The full understanding of glass properties and potentiality strongly depend on their structure. Solid State Nuclear Magnetic Resonance is very sensitive to a topological and chemical disorder around active nuclei and has arisen as the most promising experimental technique for amorphous structural elucidation[1]. Nevertheless, accurate correlations between experimental data and structural features must be found. This can be reached by a synergic experimental-computational approach that couple MD-DFT/GIPAW calculations to experimental spectra.

In this contribution we will report the investigation of the glass structure by 17O, 27Al and 29Si NMR spectroscopy [2], [3], [4]. The results evidence how network chemical disorder contributes to Qn species detection and, therefore, to network polymerization quantification. Moreover, they confirm some hypothesis made by experimentalists about the deshielding effect of Al vicinity on 29Si and 27Al nuclei.

Network modifier Ca and Na cation postions have been thoroughly investigated analyzing MD-derived models. The effect of their vicinity on NMR parameters of network nuclei can be accurately predicted and this helps in describing the limits of well known correlations that relate isotropic chemical shift to intertetrahedral angles, paving the way to the elaboration of more effective relationships[4].


33

[1] Edèn, M.; Annu. Rep. Prog. Chem., Sect. C 2012, 108, 177-221. [2] Pedone, A.; Gambuzzi, E; Malavasi, G.; Menziani, M. C.; Theo. Chem. Acc 2013, 131,

1147. [3] Pedone, A.; Gambuzzi, E; Menziani, M. C.; J. Phys. Chem. C 2012, 116, 14599−14609. [4] Gambuzzi, E.; Pedone, A.; Menziani, M. C.; Angeli, F.; Caurant, D.; Charpentier T.;

submitted to Geo. Cosmo. Acta, 2013.


34

CHARGING OF GOLD ATOMS ON DOPED MgO AND CaO:

IDENTIFYING THE KEY PARAMETERS BY DFT CALCULATIONS

Livia Giordano, Stefano Prada, Gianfranco Pacchioni

Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Cozzi 53, 20125 Milano

The use of transition metals I as dopants is a versatile way to change the properties of oxide materials. One example is the possibility to induce charge transfer from the TM to species adsorbed on the oxide surface. In the case of wide-gap alkaline-earth oxides, such as MgO and CaO, the charge transfer is determined by the respective position of the energy levels of the impurity and the adsorbate and resides in the capability of the TM to be stabilized in various oxidation states [1]. The structural and electronic properties of Cr- and Mo-doped MgO and CaO are investigated by Density Functional Theory (DFT) calculations. The problem of band gap description and energy levels alignment in DFT is addressed by comparing the results obtained with standard GGA, GGA+U and hybrid exchange-correlation functionals. The ability of the impurity ion to transfer one electron to the adsorbed species is considered for the case of electronegative Au adatoms. The study of the thermodynamic stability of the TM ions shows that Mo impurities are stable in the oxide lattice as Mo3+ or Mo+4 but can assume also higher oxidation states and are therefore able to transfer electrons to adsorbed gold. Conversely, Cr impurities are stabilized as Cr3+ and the high cost of further oxidation results in absence of charge transfer to gold on both Cr-doped MgO and Cr-doped CaO [2]. [1] Shao, X.; Prada, S.; Giordano, L.; Pacchioni, G.; Nilius, N.; Freund, H.-J. Angew. Chem.

Int. Ed. 2011, 50, 11525-11527. [2] Stavale, F.; Shao, X.; Nilius,N.; Freund, H.-J.; Prada, S.; Giordano, L.; Pacchioni, G. J.

Am. Chem. Soc. 2012, 134, 11380-11383.


35

A FIRST PRINCIPLES STUDY OF CAPPING ENERGIES AND

ELECTRONIC STATES IN PbSe NANOCRYSTALS

Fabio Grassi, Mario Argeri, Lorenzo Canti, Maurizio Cossi,

Alberto Fraccarollo, Leonardo Marchese

Dipartimento di Scienze e Innovazione Tecnologica, Centro Interdisciplinare Nanosistemi, Università del Piemonte Orientale “Amedeo Avogadro”, Viale T. Michel 11, 15121,

Alessandria, Italy. [email protected] Semiconductor quantum dots (QDs) are a relatively recent family of materials characterized by a marked dependence of physico-chemical properties on size and morphology. This intrinsic tunability makes them excellent candidates for applications in different fields such as molecular imaging, quantum computing and photovoltaics. In the present work, PbSe QDs were modelled by extracting clusters of cubic, cuboid, cuboctahedral and octahedral morphology from the cubic PbSe lattice. The effects of ligand adsorption, cluster stoichiometry and morphology on electronic structure have been investigated. Addition energies of different ligands were also calculated. Calculations were performed at DFT level with B3-LYP functional for geometry optimizations and B-LYP for electronic structures, with a modified LANL2DZ basis set with polarization functions for Pb, Se and S and 6-31G** for all other elements. Results indicate a strong dependence of electronic structure on cluster stoichiometry, with a 1:1 relationship between intra-band states and the number of excess Pb or Se atoms, whereas ligand adsorption appears to be of little influence (Figure 1). Average addition energy of capping molecules to cluster surface has been shown to decrease, albeit irregularly, as the number of adsorbed ligands increases.

Figure 1: Density of states of trimethylphosphineoxide (TMPO, top), Pb59Se56 (middle) and Pb59Se56 with adsorbed TMPO (bottom).


36

DFT-BASED DESIGN OF MOLECULAR FUNCTIONALITY:

THE CASE OF HYDROGENASES BIOMIMETIC MODELS

Claudio Greco,a Maurizio Bruschi,a Piercarlo Fantucci,b Luca De Gioiab

a Dipartimento di Scienze dell’Ambiente e del Territorio, e di Scienze della Terra, e bDipartimento di Biotecnologie e Bioscienze; Università di Milano-Bicocca,

Piazza della Scienza 1-2, 20126, Milano (Italia) [FeFe]-hydrogenases are H2-evolving enzymes featuring a Fe6S6 active site, i.e. the “H-cluster”. The latter is composed by a Fe2S2 subsite bearing CO and CN– ligands (the [2Fe]H subcluster) and a ferredoxin-like Fe4S4 subsite called “[4Fe-4S]H”. The [2Fe]H subsite directly interacts with substrates. Hundreds of synthetic complexes structurally related to the [2Fe]H site have been described so far. Many of those closely resemble the [2Fe]H geometry, but are much less efficient than the enzyme in catalysing H+ reduction. This suggests that the interplay between the [2Fe]H subcluster and the protein matrix has a central role for the enzyme function, an issue that we investigated by quantum chemical and mixed quantum/classical approaches. Theory showed that H+ binding to the [2Fe]H assembly is concomitant with e– transfer between the [2Fe]H and the [4Fe-4S]H subsites [1]. Synthetic efforts aiming at the reproduction of this key feature were later published, but proved unsuccessful. Our computational results indicated that previously used redox-active organic ligands are actually unable to establish proper electronic communication with synthetic Fe2S2 cores [2], while metallocene-based non-innocent ligands were predicted to have superior properties [2,3]. Experimental results confirmed the latter point [4]. We also used QM/MM modeling to study the process of H2 binding to the enzyme [5]; results suggest that H2 and [FeFe]-hydrogenases cellular redox partners (ferredoxins) can establish an electronic interplay of functional relevance. [1] Bruschi, M.; Greco, C.; Kaukonen, M.; Fantucci, P.; Ryde, U.; De Gioia, L. Angew.

Chem. Int. Ed. 2009, 48, 3503-3506. [2] Greco, C.; De Gioia, L. Inorg. Chem. 2011, 50, 6987-6995. [3] Greco, C. Inorg. Chem., in press. [4] Camara, ; Rauchfuss, T. B. Nat. Chem. 2012, 4, 26-30. [5] Greco, C.; Bruschi, M.; Fantucci P.; Ryde, U.; De Gioia, L. J. Am. Chem. Soc. 2011, 46,

18742-18749.


37

TOWARDS A VIRTUAL RESEARCH COMMUNITY FOR

CHEMISTRY, MOLECULAR AND MATERIALS SCIENCE

AND TECHNOLOGIES

Antonio Laganàa, Alessandro Costantinib

a Department of Chemistry, University of Perugia, Perugia, Italy b INFN, Perugia, Italy

Thanks to the progress made during the EGEE and the EGI-inspire European projects, the Chemistry, Molecular and Materials Science and Technologies (CMMST) community has set up a proposal aimed at establishing a CMMST Virtual Team (VT) of the European Grid Infrastructure (EGI) devoted to grounding the assemblage of a homonimous Virtual Research Community (see https://wiki.egi.eu/wiki/Virtual_team). Virtual Research Communities (VRCs) are groups of like-minded individuals organised by discipline or computational model. A VRC can establish a support relationship, formalised through a Memorandums of Understanding (MoU), with EGI. EGI VRCs have typically an established presence in their field and represent well-defined scientific research communities. Multi-national scientific communities can draw many benefits from having a VRC partnership with EGI. For example, they can benefit from the resources and support that are available within the National Grid Initiatives (the main stakeholders of EGI.eu), they can benefit from the workshops and forums organised by EGI, they can receive support on resolving specific technical issues with EGI services, and they become involved in the user-focussed evolution of EGI’s production infrastructure. The VT project will take the first step towards the setup of a CMMST VRC, by documenting the structure that such a VRC should have to represent the CMMST community in EGI, the technologies, resources and services that already exist within EGI and could be used to satisfy the requirements of the CMMST VRC; the technologies that need to be developed or brought into EGI, then integrated with the production infrastructure so the VRC members can efficiently manage and use TASKS. The VT will investigate how to exploit the capabilities of the existing EGI tools in building distributed workflows and “workflows of workflows” from various software packages, including - Molecular Simulators (like GEMS the Grid Empowered Molecular Simulator); - Electronic structure computation (like GAUSSIAN, GAMES, CRYSTAL, etc.); - Quantum and classical molecular dynamics computation (like ABC, GROMACS, MCTDH, VENUS96, DL_POLY, RWAVEPR, etc.);


38

- Statistical averaging to produce physical observables; - Distributed database and knowledge repositories (G-LOREP). Support to the Belong Research Laboratories endorsing the VT are: CNAF (I), UNIPG (I), UPV (ES), UB (ES), TUW (PL), Univ. Toulouse (FR), FORTH (GR), Univ. Groningen (NL), Univ. Thessaloniki (GR)


39

A VERY FAST DIVIDE AND CONQUER DISCRETIZATION

ALGORITHM FOR THE POLARIZABLE CONTINUUM MODEL

Filippo Lipparini,aBenjamin Stammb,c, Eric Cancès,dYvon Madayb,e, Benedetta Mennuccif

aUPMCUnivParis 06,Institut du Calcul et de la Simulation, 75005 Paris, France bUPMCUnivParis 06, UMR 7598, Laboratoire J.-L. Lions, 75005 Paris, France

cCNRS, UMR 7598, Laboratoire J.-L. Lions, 75005 Paris, France dCERMICS, INRIA-Ecole des Ponts, Université Paris-Est, 6 and 8 Avenue Blaise Pascal,

77455 Marne-la-ValléeCedex 2, France eDivision of Applied Mathematics, Brown University,

182 George Street, Providence, RI 02912, USA fDipartimento di Chimica e Chimica Industriale, Università di Pisa,

Via Risorgimento 35, 56126 Pisa, Italy In this contribution we present a divide and conquer method to efficiently solve the integral equations involved in the Polarizable Continuum Model1(PCM), and in particular in its Conductor-like approximation2,3, for a Van der Waals molecular cavity.The spirit of our new algorithm is the one of Schwarz Domain Decomposition method4for overlapping domains, as the spheres that form the Van der Waals cavity. On the single sphere, the Conductor-like PCM problem is diagonal in the Spherical Harmonics basis: the diagonal block (i.e., the one associated to a specific sphere) of the matrix obtained with our algorithm will be diagonal. Furthermore, as only the spheres overlapping with the reference one will give contributions, the matrix is also block sparse for large molecules: linear scaling with respect to the dimension of the system can be easily obtained using a simple Jacobi iterative scheme. The Jacobi scheme allows for an embarrassingly parallel implementation, which, together with the linear scaling properties of the algorithm, result in a very fast computation of the solvation energy. [1] Tomasi, J.; Mennucci, B.; Cammi, R.Chem. Rev. 2005, 105, 2999-2093. [2] Klamt, A.; Schuurmann, G. J. Chem. Soc., Perk. Trans. 1993, 2, 799-805. [3] Barone, V.; Cossi, M. J. Phys. Chem. A 1998, 102, 1995-2001. [4] Schwarz, H.A. Vierteljahrsschrift der NaturforschendenGesellschaft in Zürich 1870, 15,

272-286.


40

CATALYTIC MECHANISM OF THE ARYLSULFATASE

PROMISCUOUS ENZYME

Tiziana Marino, Nino Russo

Department of Chemistry, Università della Calabria 87036, Arcavacata di Rende (Italy)

The Pseudomonas aeruginosa aryl sulfatase (PAS) enzyme catalyzes the hydrolysis of the original p-nitrophenyl-sulfate (PNPS) substrate such as that of the promiscuous p-nitrophenyl-phosphate (PNPP) one with comparable kinetics.

Figure: Active site of the PAS and its two substrates. With the aim of elucidating the working mechanism of this enzyme having “broad substrate specificity”, a full quantum chemical study has been performed at the density functional level [1]. Although the potential energy surfaces of the two examined reactions are almost similar, the rate determining step is different (nucleophile attack for PNPS versus nucleophile activation for PNPP). The calculated ∆∆G between two reactions (0.7 kcal/mol) is in agreement with that obtained converting to barriers the available experimental kinetic data (1.6 kcal/mol, applying classical transition-state theory) at the same temperature (T=298.15 K). Furthermore, the influence of the dispersion contributions on both investigated reactions has been also taken into account. [1] Marino T.; Russo N.; Toscano M. Chem.-Eur. J, DOI:10.1002/chem.201201943.


41

UNVEILING STRUCTURE-PROPERTY RELATIONSHIPS IN

PEROVSKITE-OXIDE BASED ELECTRODES FOR SOLID OXIDE

FUEL CELL APPLICATIONS

Ana B. Muñoz-García,a Michele Pavone,a Emily A. Carter b

a Dipartimento di Scienze Chimiche, Universitá di Napoli Federico II, Comp. Univ. M. S. Angelo, Via Cintia 21, 80126 Napoli. [email protected]

b Department of Mechanical and Aerospace Engineering, Program in Applied and Computational Mathematics, and the Andlinger Center for Energy and the Environment,

Princeton University, Princeton, NJ, 08544-5263 USA. Solid oxide fuel cell (SOFC) devices generate electricity and high-quality heat with high efficiency and low pollution from flexible fuel sources. However, current SOFCs operate at temperatures too high (900-1000°C) to be effective in terms of materials durability, thus limiting widespread use of this technology. Therefore, considerable effort is being devoted to developing new SOFCs that can operate at lower, intermediate temperatures (600-800°C). In many cases, the cathode material poses the greatest challenge. It is difficult to simultaneously retain adequate oxygen reduction reaction (ORR) rates and high oxide ion mobility at intermediate temperatures. Complex perovskite-type transition metal oxides have been the materials of choice. The key factors determining the relative usefulness of these materials are: high-temperature stability, ability to catalyze the ORR at reasonable rates and sufficiently high electronic conductivity. In this talk, simple quantum mechanical analyses of LaMO3 (M = Cr, Mn, Fe, Co) materials will be discussed, providing new insights into what drives the relative ease of formation of oxygen vacancies, which is a prerequisite for and predictor of oxide ion bulk diffusion [1]. Moreover, a promising new SOFC electrode material based on Sr2Fe(1+x)Mo(1-x)O6-δ (SFMO) will be presented [2, 3]. In particular, the theoretical analysis of the electronic structure allows us to elucidate the origin of SFMO non-stoichiometry and the attendant mixed ion-electron conductor character so important for intermediate temperature fuel cell operations. [1] Pavone, M.; et al., Energy Environ. Sci. 2011, 4, 4933-4937. [2] Muñoz-García, A. B.; et al., Chem. Mater. 2011, 23, 4525-4536. [3] Muñoz-García, A. B.; et al., J. Am. Chem. Soc. 2012, 134, 6826-6833.


42

MASSIVELY PARALLEL CRYSTAL PROGRAM FOR LARGE UNIT

CELL AB INITIO CALCULATIONS

Roberto Orlando

Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125 Torino. The electronic structure and properties of crystals can be calculated ab initio with CRYSTAL [1] at different levels of approximation ranging from Hartree-Fock (HF) to Kohn-Sham (KS) Density Functional Theory (DFT), including use of hybrid functionals. The CRYSTAL program is based on the use of Gaussian-type orbitals, which allows easy interpretation of the electronic structure and direct comparison with molecular fragments. The present release of the code, CRYSTAL09 (http://www.crystal.unito.it), enables fully automated and efficient search for minimum energy structures and the computation of a variety of properties including structural, elastic, piezoelectric, dielectric, magnetic and electronic properties, simulation of vibration spectra. Extensive use of symmetry and low computational requirements make the program efficient and suitable for the study of complex structures with ordinary computer facilities. Use of standard parallel linear algebra libraries now permit large-scale calculations for systems containing thousands of atoms in the unit cell with good scalability over thousands of processors on High Performance Computers (HPC). In the impending new release of the program memory storage has been fully reorganized and optimized with removal of all static limits; data distribution is also enhanced [2]. Thus, crystals containing more than 100000 basis functions in the unit cell can now be handled efficiently and quasi-linear scaling with the unit cell size has been achieved on HPCs. Full parallelization has also been extended to the calculation of the full set of “properties” available in CRYSTAL. The new capabilities of the program, which enable investigation of complex problems such as materials in the nanoscale [3] or biological systems [4], will be illustrated. [1] Dovesi, R.; Orlando, R.; Civalleri, B.; Roetti, C.; Saunders, V. R.; Zicovich-Wilson, C.

M. Z. Kristallogr. 2005, 39, 571-573. [2] Orlando, R.; Delle Piane, M.; Bush, I. J.; Ugliengo, P.; Ferrabone, M.; Dovesi, R. J.

Comput. Chem. 2012, 33, 2276–2284. [3] Garcia-Castello, N.; Prades, J. D.; Orlando, R.; Cirera, A. J. Phys. Chem. C 2012, 116,

22078–22085. [4] Rimola, A.; Aschi, M.; Orlando, R.; Ugliengo, P. J. Am. Chem. Soc. 2012, 134,

10899−10910.


43

N

N

C4H9

C4H9Local

Excitation (LE)

Charge-Transfer

(CT) Excitation

Po

ten

tia

lE

ne

rgy

Su

rfa

ces

(eV

)

Solvation Coordinate

LE

emission

CT

emission

Non-polar solvent Polar solvent

TUNING THE NATURE OF THE FLUORESCENT STATE:

A SUBSTITUTED POLYCONDENSED DYE AS A CASE STUDY

Cristina Sissa,a Valentina Calabrese,b Marco Cavazzini,b Luca Grisanti,a Francesca Terenziani,a Silvio Quici,b Anna Painellia

a Dipartimento di Chimica Università di Parma and INSTM UdR-Parma b Istituto di Scienze e Tecnologie Molecolari (ISTM) CNR

We present an extensive spectroscopic analysis of an elongated polycondensed dye with donor–acceptor substitution. The charge-transfer (CT) state, polarized along the long molecular axis, is close in energy to a local excitation (LE) of the polycondensed system, roughly polarized along the short molecular axis, making this system particularly suitable to investigate the LE/CT interplay. An essential-state model is presented that quantitatively reproduces absorption and fluorescence spectra, as well as fluorescence emission and excitation anisotropy spectra collected in solvents of different polarity and viscosity. A sound basis is set for the understanding of how relaxation of polar solvents affects the nature of low-lying excitations. The markedly different fluorescence emission and excitation anisotropy spectra measured in glassy and liquid polar solvents unambiguously demonstrate the major role played by solvent relaxation in the definition of fluorescence properties of the dye.1

[1] C. Sissa et al., Chem. Eur. J. 2013, 19, 924 – 935.


44

AB-INITIO DFT+U STUDY OF Sr-DOPED LaMO 3 (M=Cr, Mn)

Michele Pavone,a Ana B. Muñoz-Garcia,a Emily A. Carterb

a Dipartimento di Scienze Chimiche, Universitá di Napoli Federico II, Comp. Univ. M. S. Angelo, Via Cintia 21, 80126 Napoli. [email protected]

b Department of Mechanical and Aerospace Engineering, Program in Applied and Computational Mathematics, and the Andlinger Center for Energy and the Environment,

Princeton University, Princeton, NJ, 08544-5263 USA. Perovskite-type transition metal oxides have many technological applications, from solid oxide fuel cells (SOFC) to oxygen and proton membranes, from colossal magneto-resistance to ferroelectric devices. The key to such a success is the ease of tuning the ABO3 chemical formula with aliovalent substitutions at the A and/or B sites. The resulting p-/n-doped electronic structure alters and determines the properties of the perovskite. Therefore, proper modelling of these features is crucial to support and guide a rational design of new and more effective materials. In this contribution we will discuss the cases of La(1-

x)Sr(x)CrO3 (LSC) and La(1-x)Sr(x)MnO3 (LSM) with x equal to 0 and 0.25. Both LSC and LSM have been successfully applied as SOFC interconnects and cathodes, respectively [1]. The presence of holes formed upon Sr substitution for La affects the transition-metal d-states and induces formation of M4+ species. The very localized nature of transition metal d-orbitals and the well-known self-interaction error (SIE) of standard density functional theory (DFT) makes it challenging to capture the correct physics of these materials. Within this context, we will discuss the ab initio DFT+U approach [2] and will compare its performance against the very popular PBE semi-local density functional [3] and the HSE06 hybrid functional [4]. Our results show how important it is to correct the SIE in order to produce accurate electronic features and also for gaining important insights into the charge and oxide transport mechanisms in these materials [5]. [1] Ishihara, T. (Ed.) Perovskite Oxide for Solid Oxide Fuel Cells, Springer, 2009. [2] Mosey, N.J.; et al. J. Chem. Phys. 2008, 129, 014103. [3] Perdew, J.P.; et al., Phys. Rev. Lett. 1996, 77, 3865-3868. [4] Heyd, J.; et al., J. Chem. Phys. 2006, 124, 219906. [5] Pavone, M.; et al., Energy Environ. Sci. 2011, 4, 4933-4937.


45

A STRATEGY FOR NONADIABATIC QUANTUM-CLASSICAL

DYNAMICS OF SEMIRIGID MOLECULES. INVESTIGATING THE

PHOTOSTABILITY OF NUCLEOBASES

David Picconi,a Francisco José Avila Ferrer,b,c Roberto Improta,d Alessandro Lami,b Fabrizio Santorob

a Technische Universit�t München, Lehrstuhl für Theoretische Chemie, Lichtenbergstraße 4, D-85747 Garching, Germany

b Consiglio Nazionale delle Ricerche, Istituto di Chimica dei Composti OrganoMetallici (ICCOM-CNR), UOS di Pisa, Area della Ricerca, via G. Moruzzi 1, I-56124 Pisa, Italy c University of Málaga, Physical Chemistry, Faculty of Science, Málaga 29071, Spain

d Consiglio Nazionale dell Ricerche, Istituto di Biostrutture e Bioimmagini (IBB-CNR), via Mezzocannone 16, I-80134, Napoli, Italy

Semirigid molecules, whose excited state behaviour has an essentially vibrational nature, are of great importance in many fields of photochemistry. Particular interest is devoted to the description of the dynamical processes occurring after a photoexcitation to a set of nonadiabatically coupled electronic states. The theoretical simulation by means of quantum wave packet propagations represents one of the best ways to describe the quantum effects of the molecular motion, thus the internal conversion processes. Besides, this opens the route to the description of nonadiabatic effects in different spectroscopic signals, by means of eigenstate-free time-dependent calculations.[1] The purpose of this contribution is to illustrate a general time-dependent procedure to study the photophysics of internal conversion processes in large semirigid molecules. With this intent, we model the potential energy surfaces within the most general quadratic approximation, thus including the Duschinsky mixing between normal modes, and describing the inter-state coupling through a term linear in the coordinates.[2] This model is reminescent to those routinely used for the eigenstate-based computations of single-state vibronic spectra.[3] The dimensionality of the system is reduced with a rigorous standard approach, which has been developed recently,[4] and allows to define a new set of coordinates partitioned into groups, defining a hierarchy of effective Hamiltonians, depending on few ad hoc degrees of freedom, for which the time-dependent Schrödinger equation can be solved exactly. The different quantum dynamical results (state populations, spectra) converge rapidly going on with the hierarchy, and it is shown that the convergence improves when the remaining coordinates are included as a ‘classical bath’.[5]


46

As an example, it will be illustrated how this scheme was applied to the simulation of ππ*/nπ* internal conversions in nucleobases, a process whose importance for the DNA photostability is intensely debated in literature. [1] Lami, A.; Santoro F. in Computational Strategies for Spectroscopy: from Small

Molecules to Nanosystems, edited by V. Barone, chap. 10, p. 475 (wiley, Chichester, UK, 2010).

[2] Köppel, H.; Domcke, W.; Cederbaum, L. S. Adv. Chem. Phys. 1984, 57, 59. [3] Biczysko, M.; Bloino, J.; Santoro, F.; Barone, V. in Computational Strategies for

Spectroscopy: from Small Molecules to Nanosystems, edited by V. Barone, chap. 8, p. 361 (wiley, Chichester, UK, 2010).

[4] Picconi, D.; Lami, A.; Santoro, F. J. Chem. Phys. 2012, 136, 244104. [5] Picconi, D.; Avila Ferrer, F. J.; Improta, R.; Lami, A.; Santoro, F. Faraday Discuss.

2012, 163.


47

BENCHMARKING PERIODIC DISPERSION-CORRECTED DFT

CALCULATIONS FOR THE PREDICTION OF MOLECULAR

CRYSTAL POLYMORPHISM


Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia,

Via G. Campi 183, 41125 Modena, Italy Periodic Density Functional Theory (DFT) calculations employing the PBE, PBE0 and B3LYP functionals coupled with different dispersion-correction schemes (-D and –TS) have been applied to the para-diiodobenzene (p-DIB) molecular crystal in order to determine how they perform in reproducing the energetic and crystal geometry of its two well known polymorphs. Our results [1] showed that, when properly corrected, DFT calculations successfully predict the relative stability of the α (Fig.1) and β phases at zero temperature, in good agreement with Diffusion Monte-Carlo (DMC) calculations [2]. Among the two dispersion corrections employed, the recently proposed Tkatchenko and Scheffler (TS) scheme [3] performs much better than the original Grimme scheme (D) [4]. This is imputable to the accurate nonempirical method used to obtain the dispersion coefficients in the former approach. We are currently benchmarking the TS scheme also against a polar system, such as the oxalyl dihydrazide (Fig.2). This simple molecule gives rise to five different phases, in which the competition of intermolecular H-bond and dispersive interactions makes the prediction of the relative stability very challenging. The TS scheme leads to a nice agreement with experiment both for structures and thermodynamics. The TS and other analogous models for dispersion-correction are still not commonly used in computational chemistry but the results reported in literature denote the accuracy of such methods to describe long-range interactions. In our opinion, they can play a fundamental role to better understand the chemical and physical nature of weak interactions – not only in the field of molecular crystals – opening a new era for the design and the prediction of increasingly complex systems, as requested from the market.


48

[1] Pedone A.; Presti D.; Menziani M.C.; Chem. Phys. Lett. 2012, 541, 12-15. [2] Hongo K.; Watson M. A.; Sànchez-Carrera R. S.; Iitaka T.; Aspuru-Guzik A.; J. Phys.

Chem. Lett. 2010, 1, 1789. [3] Tkatchenko A.; Scheffler M.; Phys. Rev. Lett. 2009, 102, 073005. [4] Grimme S.; J. Comput. Chem. 2006, 27, 1787.


49

COMPUTATIONAL INVESTIGATION OF IR SPECTRA OF

ELECTROSPRAY IONIZED BIOMOLECULES

Roberto Paciotti,a Cecilia Coletti,a Nazzareno Re,a Maria Elisa Crestoni, b

Simonetta Fornarinib

a Dipartimento di Farmacia, Università G. d’Annunzio Chieti-Pescara, Via dei Vestini, 66100 Chieti

b Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma La Sapienza, P.le A. Moro 5, 00185, Roma, Italy.

IR vibrational spectroscopy is a widespread technique for the characterization of molecules in gas phase, allowing the detection of motifs and signatures occurring in relevant processes. In particular, IR spectroscopy of organic molecules is known to be highly sensitive to hydrogen bonding, a feature that makes this technique very appealing for a detailed structural characterization. The extremely low density of gas phase ions requires the use of a sensitive ‘action’ spectroscopy approach such as IRMPD (IR Multiple Photon Dissociation). The interpretation of the experimental spectra needs a strong computational support to correctly assign the main features corresponding to the vibrational signatures and to identify populated isomers and/or conformers, particularly when processes involving aminoacids or peptides are investigated. However, the computed spectrum is extremely sensible to the employed level of theory [1], to the basis set size and to the inclusion of anharmonicity effects in the calculation [2]. Furthermore, because IRMPD experiments are carried out at room temperature, the contribution of all the accessible conformers has to be considered [3]. In this work, the effect of all these aspects was individually taken into account to accurately reproduce the IRMPD spectrum of the O-sulfoserine anion and cation, paying special attention to the characterization of the sulfonation vibrational signatures. Indeed, sulfonation occurs as a common enzymatic modification of endogenous substances and drugs and has recently been discovered and characterized in serine and threonine residues. [1] Zevereva, E.E.; Shagidullin, A.R.; Katsyuba, S.A. J. Phys. Chem. A 2011, 115, 63-69. [2] Barone, V. J. Chem. Phys. 2004, 120, 3059. [3] C. Coletti , N. Re, D. Scuderi, Ph. Maitre, B. Chiavarino, S. Fornarini, F. Lanucara, R.K.

Sinhayc, M.E. Crestoni, Phys.Chem.Chem.Phys., 2010, 12. 13455-13467.


50

STRUCTURE AND DYNAMICS OF HYDRATED Na VERMICULITE

CLAY STUDIED BY CAR-PARRINELLO MOLECULAR DYNAMICS

SIMULATIONS

Giuseppe B. Suffritti,a Pierfranco Demontis,a Marco Masia,a,b

a Dipartimento di Chimica e Farmacia, Università degli studi di Sassari, and Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM),

Unità di ricerca di Sassari, Via Vienna, 2, I-07100 Sassari b Istituto Officina dei Materiali, CNR, UOS SLACS, Via Vienna 2, 07100 Sassari

Car-Parrinello molecular dynamics simulations are applied to unravel the structure of vermiculite clay at the hydration level found in the natural mineral. The structure and the vibrational spectra of the aluminosilicate sheet is well known and is well reproduced by the simulations. However, the structures of the interlayer content at the ambient conditions, Na cations and hydration water molecule (4 H2O per Na+), as proposed in X-ray diffraction experimental papers seemingly are not in full agreement with the results of neutron diffraction experiments found in literature, yielding only the density profile perpendicular to the aluminosilicate sheets, but including hydrogens. Our calulations reproduce this density profile, and show that the interlayer content is remakably disordered, with some Na cations located midway between the sheets and some others lying closer to the to the clay surface. The amount of the adsorbed water is not sufficient to form a complete hydration shell for the cations, nor a continuous hydrogen bond network, as most water molecules are also hydrogen bonded to the basal oxygens of the sheets. Anomalous Na+ – Na+ and water – water radial distribution functions suggest the presence two different Na+ – Na+ distances, depending on the interposition of water between cations, which indeed were found by X-ray diffractions, and loose water – water hydrogen bonds. On the other hand, X-ray diffraction studies proposed a more symmetric distribution of water and cations, but were able to locate only about one half of the interlayer content, as the occupancies of all atoms were partial. The symmetric distributions probably were originated by the constraints of the crystal symmetry group chosen for the structure refinement. Yet, at least for the cations, the average computed positions, although affected by large errors, are compatible with those reported in the experimental works. By adding two more water molecules per Na+, a completely different structure of the interlayer content results from the calculations. Water molecules form two parallel plane sheets showing an unusual hexagonal structure and the cations remain midway between the sheets at crystallographic positions and at regular distances.


51

DENSITY FUNCTIONAL THEORY FOR MOLECULAR

MULTIPHOTON IONIZATION

IN THE PERTURBATIVE REGIME

Daniele Toffoli,a Piero Declevab

a Department of Chemistry, Middle East Technical University, 06531 Ankara, Turkey. b Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Trieste, Via L. Giorgieri 1, I-34127, Trieste, Italy and CNR-IOM DEMOCRITOS, Trieste, Italy

A general implementation of the lowest nonvanishing order perturbation theory for the calculation of molecular multiphoton ionization cross sections is proposed in the framework of density functional theory. Bound and scattering wave functions are expanded in a multicentric basis set and advantage is taken of the full molecular point group symmetry, thus enabling the application of the formalism to medium-size molecules. Multiphoton ionization cross sections and angular asymmetry parameters have been calculated for the two- and four-photon ionization of the H2

+ molecule, for linear and circular light polarizations. Both fixed and random orientations of the target molecule have been considered. To demonstrate the efficiency of the proposed methodology, the two-photon cross section and angular asymmetry parameters for the HOMO and HOMO-1 orbital ionization of benzene are also presented.


52

SPATIAL AND ELECTRONIC CORRELATIONS IN THE PE545

LIGHT-HARVESTING COMPLEX

Lucas Viani a, Carles Curutchet b, Benedetta Mennucci a

a Dipartimento di Chimica e Chimica Industriale, Università di Pisa,

via Risorgimento 35, 56126 Pisa, Italy b Departament de Fisicoquímica, Facultat de Farmàcia, Universitat de Barcelona,

Av. Joan XXIII s/n, 08028 Barcelona, Spain The recent discovery of long-lasting quantum coherence effects in photosynthetic pigment–protein complexes has challenged our view of the role that protein motions play in light-harvesting processes. Several groups have suggested that correlated fluctuations involving the pigments site energies and couplings could be at the origin of such unexpected behavior. Here we combine molecular dynamics simulations with quantum mechanics/molecular mechanics calculations to analyze the degree of correlated fluctuations in the PE545 complex of Rhodomonas sp. strain CS24. We find that correlations between the motions of the chromophores, which are significantly assisted by the water solvent, do not translate into appreciable site energy correlations but do lead to significant cross-correlations of energies and couplings. Such behavior, not observed in a recent study on the Fenna–Mathews–Olson complex, seems to provide phycobiliproteins with an additional fundamental mechanism to control quantum coherence and light-harvesting efficiency compared with chlorophyll-containing complexes.


53

H-TRANSFER TERMINATION MECHANISMS IN POLYOLEFIN

HOMOGENEOUS CATALYSIS

Vincenzo Villani, Gaetano Giammarino

Dipartimento di Scienze, Università degli Studi della Basilicata, Campus di Macchia Romana, Potenza (Italy)

The understanding of the reaction mechanisms in homogeneous polymerization of olefins is today a challenging topic1-3. Fujita et al.1 have been the first to highlight the living behaviour, in which the ability of the polymer chain to terminate is removed, in post-metallocene Ti-based catalysts.

Mecking et al.2 showed that the bis(enolatoimine)Ti catalyst, with ortho-fluorinated aryl groups, is also able to achieve the same living behaviour. Via NMR, the key role of F-bond interactions was proposed. We study Mecking’s catalysts, using DFT calculations on a parallel platform running GAUSSIAN09, at the triple ζ plus polarization with Becke-Perdew exchange-correlation level. The stationary structures have been localized and energy barriers of activation determined. Normal mode analysis and intrinsic reaction coordinates have been performed. The key role

of fluorine interactions both in propagation and termination steps has been made clear. An alternative H-transfer to the ligand in the termination mechanism is proposed. [1] Terao, H.; Iwashita, A.; Matsukawa, N.; Ishii, S.; Mitani, M.; Tanaka, H.; Nakano, T.;

Fujita, T. ACS Catal. 2011, 1, 254-265. [2] Bryliakov, K. P.; Talsi, E. P.; Möller, H. M.; Baier, M. C.; Mecking, S. Organometallics

2010, 29, 4428-4430. [3] Villani, V.; Giammarino, G. Macromolecules 2010, 43, 5917-5918.


54


55

COMUNICAZIONI POSTER


56


57

FULLY AUTOMATED PROCEDURE TO EVALUATE ELASTIC AND

PIEZOELECTRIC CONSTANTS

Elisa Albanese, Alessandro Erba, Bartolomeo Civalleri

Dipartimento di Chimica e Centro di Eccellenza NIS, Università di Torino, via Pietro Giuria 7, Torino, 10125, ITALIA

A fully automated procedure to evaluate the independent second- and third-order elastic constants (SOEC and TOEC) and piezoelectric coefficients has been implemented in the periodic ab-initio CRYSTAL[1] code. This procedure can handle any space group of 1D, 2D and 3D periodic systems. The automated scheme provides, by exploiting the symmetry, to find the minimal set of strains required to get all the independent coefficients and then apply them to the unstressed structure. This procedure was partially already implemented for the SOEC[2], but only now it has been made fully automatic and extended to TOEC and piezoelectricity calculation. The SOEC are related to the strain second derivatives of the total energy, and the TOEC, that provide information on the nonlinear elasticity of the materials, to the strain third derivatives:

in which Voigt’s notation is used (I, j, k = 1, 2, ..., 6) and V is the equilibrium volume. The evaluation of elastic constants is accomplished by using a stress-strain relationship based on a total energy calculation, then second and third derivatives of the energy as a function of crystal deformation are numerically evaluated by means of the analytical gradients. The approach used for computing the piezoelectric coefficients involves the computation of the intensity of polarization induced by strain through the Berry phase’s (BP) theory[3]. In short, the piezoelectric constants are related to the derivatives of BP φ with respect to the strain components εk according to:

where e is the electron charge and aji is the i-th cartesian component of the j-th direct lattice basis vector aj. Different systems are used to test the numerical stability and the accuracy of the new procedure, especially for the piezoelectric constants and TOEC that appear more delicate than for the SOEC[2]. α-quartz and ZnO have been selected as test cases for piezoelectric constants and silicon for TOEC. Furthermore, the effect of the DFT functionals on the piezoelectric coefficients has been analysed. [1] Dovesi, R. et. al. CRYSTAL09 User’s Manual. University of Torino: Torino, 2009. [2] Pergen, W. F.; Criswell, J.; Civalleri B.; Dovesi R. Comp. Phys. Comm., 2009, 180,

1753-1759. [3] Catti M.; Noel Y.; Dovesi.R. J. Phys. Chem. Solids, 2003, 11, 2183.


58

DFT AND TDDFT STUDY OF UNSYMMETRICAL SQUARAINES

ADSORBED ON PbSe SURFACES

Mario Argeri,a Claudia Barolo,b Maurizio Cossi,a Fabio Grassi,a

Leonardo Marchesea

a DISIT, Università del Piemonte Orientale A. Avogadro, Viale Teresa Michel 11, 15121 Alessandria, Italy

b Department of Chemistry, NIS Centre of excellence, Università di Torino, Via Pietro Giuria 7,10125 Torino, Italy

Recently considerable efforts have been spent to study Dye Sensitized Solar Cells (DSSC), which represent an attractive alternative to traditional solid state technology for converting sunlight to electricity at low cost. Several kinds of dyes are employed as sensitizers and among them the most successful in obtaining high power conversion efficiency (PCE) are the ruthenium polypyridyl complexes, yelding above 11% PCEs. In spite of this good level of efficiency, the main disadvantage of the Ru-complexes is the lack of absorption in the far-red/near IR region. To improve the absorption capacity of the dye layer, new sensitizers, characterized by a wider spectral match with the solar emission, have been recently explored. Among the different classes of near-IR dyes, squaraines received a special attention due to their good photo- and thermal stability and the research is mainly focused on unsymmetrical squaraines, rather than on symmetric ones, since it is thought that this asymmetry favors the directionality of the charge transfer. One recent advancement in photovoltaics technology is the use of semiconductor quantum dots (QDs) as sensitizers: such devices are known as Quantum Dot Sensitized Solar Cells (QDSSCs). This line of research has attracted considerable interest due to the tunability of the QD band gap and to multiple exciton generation (MEG), that is the production of several electron-hole bound states by means the absorption of a single photon, which in principle enables to overcome the Shockley-Queisser efficiency limit. One of the most promising semiconductor materials for the purpose above is the Lead Selenide, PbSe, within which the MEG takes place, although the quantum yield of such process is still debated. It is believed that the use of a squaraine dye as a linker molecule between the PbSe QD and the TiO2 layer could be a possible further research development. In this work we study the adsorption properties of some unsymmetrical squaraines, coded as VG0 and VG0-NH2 , on PbSe surfaces in order to investigate the stability of PbSe-squaraine adduct. Furthermore we calculate at TDDFT level the absorption spectra of squaraines above both in the free and adsorbed case to gain insight about changes in dye’s optical properties due to the adsorption on PbSe.


59

[1] C. Barolo, M.Graetzel, M. Nazeeruddin et. al. Chem. Commun. 2012, 48, 2782-2784.


60

MODELING OF SPIRAL HALLOYSITE NANOTUBES

Francesco Ferrante, Nerina Armata, Giuseppe Lazzara, Stefana Milioto

Dipartimento di Fisica e Chimica – Università degli Studi di Palermo, viale delle Scienze Ed. 17 I-90128 Palermo

Halloysite is an economically viable clay mineral, belonging to the kaolinite group and occurring in nature with a hollow tubular shape. The size of halloysite nanotubes are between 500 and 1000 nm in I and 15-100 nm in inner diameter, depending on the deposit. The general stoichiometry is Al2Si2O5(OH)4·n H2O with n=0 for the anhydrous (Halloysite 7Å) and n=2 for the fully hydrated halloysite (Halloysite 10Å). The crystal structure is described as a layer formed by two building blocks: [SiO4] tetrahedra and [AlO6] octahedra. Water molecules in Halloysite 10Å are sitting between two consecutive layers. This material finds application in ceramics, cements and fertilisers industry and, recently, as template in nanotechonology. In fact, thanks to its peculiar shape, halloysite is considered a promising entrapment system for loading, storage and controlled release system for various species [1]. The modeling approach is an helpful tool in the prediction and interpretation of the interactions occuring between adsorbed species and inner and/or outer nanotube surfaces. Even though a preliminary study on the adsorption process could be obtained from a flat monolayer of kaolinite model or single-walled halloysite nanotube [2], it is necessary to build up a more realistic model of the hollow spiral nanotube. To this aim the starting geometries of Halloysite 7Å and Halloysite 10Å have been generated by means of a program based on the analitycal properties of Archimedean spiral. Geometry optimization of the supercells so obtained (some of which exceed 2500 atoms) has been perfomed by means of Self Consistent Charges Density Functional Tight Binding employing the DFTB+ program [3]. These investigations, which represent the first attempts to model the hydrated halloysite spiral nanotube, allowed to obtain information on the [SiO4] tetrahedra and [AlO6] octahedra distortions necessary to the spiral formation and on the water molecules organization on the Halloysite 10Å outer surfaces and between the arms of its spiralling geometry. [1] Lvov, Y. M., et al. ACS Nano 2008, 2, 814-820. [2] Guimarães, L., et al. J. Phys. Chem. C 2010, 114, 11358-11363. [3] Aradi B., et al. J. Phys. Chem. A 2007, 111, 5678-5684.


61

IMPROVING THE COMPARISON OF COMPUTATIONAL DATA

WITH EXPERIMENTAL ABSORPTION AND EMISSION SPECTRA.

BEYOND THE VERTICAL TRANSITION APPROXIMATION

Francisco Avila,a,b Javier Cerezo,c Emiliano Stendardo,d

Roberto Improta,d Fabrizio Santoroa

a CNR–Consiglio Nazionale delle Ricerche, Istituto di Chimica dei Composti Organo Metallici (ICCOM-CNR), UOS di Pisa, Area della Ricerca,

via G. Moruzzi 1, I-56124 Pisa, Italy b University of Málaga, Physical Chemistry, Málaga, 29071, Spain

c Departamento de Química Física, Universidad de Murcia, 30100 Murcia, Spain d CNR–Consiglio Nazionale delle Ricerche, Istituto di Biostrutture Biommagini (IBB-CNR)

Via Mezzocannone 16, I-80136, Napoli, Italy. E-mail: [email protected]

We carefully investigate the relationship between computed data[1.2] and experimental electronic spectra. We compare vertical transition energies EV and characteristic features of the spectrum like the maximum max and the first moment M1, taking advantage on an analytical expression of M1 of an electronic spectrum in terms of the initial and final-state potential energy surfaces, allows to investigate the molecular factors that cause their differences. Simulations of the absorption and emission spectra of several prototypical chromophores gives lineshapes in very good agreement with experiments. Analysis of the simulated spectra reveals that differences among EV, max and M1 are of the order of tenths of eV, i.e. comparable to the expected accuracy of the most accurate computational methods. Our results indicate that the customary comparison of experimental max and computational EV, without taking into account vibrational effects, is no more an adequate measure of the performance of an electronic method, whereas comparison of M1 and/or 0-0 transition frequencies provides more robust results. Some rules of thumbs are proposed to help rationalize which kind of correction one should expect when comparing EV, M1 and max.[3]

[1] Santoro, F.; Fcclasses a Fortran 77 code, 2008 http://village.pi.iccom.cnr.it [2] Avila Ferrer F. J.; Santoro F. Phys. Chem. Chem. Phys. 2012, 14, 13549-13563. [3] Avila Ferrer, F. J.; Cerezo, J.; Stendardo, E.; Improta, R.; Santoro, F. Submitted.

Figure 1 Schematical relationship

between spectral and computed


62

BERYLLIUM OXIDE NANOTUBES AND THEIR CONNECTION TO

THE FLAT MONOLAYER

J. Baima,a A. Erba,a M. Rérat,b R. Orlando,a R. Dovesia

a Dipartimento di Chimica and Centre of Excellence NIS (Nanostructured Interfaces and Surfaces), Università di Torino, via Giuria 5, IT-10125 Torino (Italy)

b Equipe de Chimie Physique, IPREM UMR5254, Universit � de Pau et des Pays de l’Adour, FR-64000 Pau (France)

Single-walled zigzag Beryllium Oxide (BeO) nanotubes are simulated with an ab initio quantum chemical method. The (n,0) family is investigated in the range from n = 8 (32 atoms in the unit cell and tube radius R = 3.4 Å) to n = 64 (256 atoms in the cell and R = 27.1 Å). The trend towards the hexagonal monolayer (h-BeO) in the limit of large tube radius R is explored for a variety of properties: rolling energy, elastic modulus, piezoelectric constant, vibration frequencies, infrared (IR) intensities, oscillator strengths, electronic and nuclear contributions to the polarizability tensor. Three sets of IR-active phonon bands are found in the spectrum. The first one lies in the 0 – 300 cm-1 frequency range and exhibits a very peculiar behavior: the vibration frequencies do tend regularly towards zero when R increases while their IR intensities do not; the nature of these normal modes is unveiled by establishing a connection between them and the elastic and piezoelectric constants of h-BeO. The second (680 – 730 cm−1 ) and third (1000 – 1200 cm−1 ) sets tend regularly, but with quite different speeds, to the optical modes of the h-BeO layer. The vibrational contribution of these modes to the two components (parallel and perpendicular) of the polarizability tensor is also discussed. Simulations are performed using the Crystal program which fully exploits the rich symmetry of this class of one-dimensional periodic systems: 4n symmetry operators for the general(n,0) tube.


63

THE NEAR-EDGE X-RAY-ABSORPTION FINE-STRUCTURE OF O 2

CHEMISORBED ON Ag(110) SURFACE STUDIED BY DENSITY

FUNCTIONAL THEORY

Oscar Baseggioa, Mauro Stenera,b, Michele Romeoa, Giovanna Fronzonia,b

a Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Trieste, Via L. Giorgieri 1, I-34127 TRIESTE – ITALY

bConsorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali, INSTM, Unità di Trieste

The adsorption of O2 on the silver surface has been studied since many decades, since it has important implications in the oxygen dissociation, in the oxidation of surface and in catalytic processes. In the present work the NEXAFS at the O K edge of O2 adsorbed on the Ag(110) surface has been calculated employing a DFT methodology, while the surface has been simulated employing finite size clusters of large size (Ag156). Although the infinite nature of the surface would lead to employ computational schemes with periodic boundary conditions, the NEXAFS process, where the core hole transition is very localized on a specific atomic site, can be properly described with cluster models of finite size. This has two important practical advantages: first molecular quantum chemistry codes can be directly applied to describe this phenomenon, second most implementations with periodic boundary conditions cannot describe properly core orbitals due to the cutoff of plane wave momentum, problem which is circumvented introducing pseudopotentials. Present NEXAFS spectra have been calculated from dipole transition moments between initial core orbital and final virtual one, taking the dipole component along the electric vector polarization and employing a code developed in the authors research group [1]. Comparison between experimental [2] and present calculated NEXAFS allows a clear assignment of the spectral features as well as some suggestions about a deviation from the ideal adsorption geometry. [1] Fronzoni, G.; Balducci, G.; De Francesco, R.; Romeo, M.; Stener, M. J. Phys. Chem. C,

2012, 116, 18910-18919. [2] Pawela-Crew, J.; Madix, R. J.; Stöhr, J. Surf. Sci. 1995, 339, 23-28.


64

FUNCTIONAL EFFECTS ON THE TDDFT INVESTIGATIONS IN

ORGANOMETALLIC PHOTOCHEMISTRY

Luca Bertini,a Maurizio Bruschi,b Claudio Greco,b Luca De Gioia,a

Piercarlo Fantucci,a Giuseppe Zampellaa

a Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca Piazza della Scienza, 2; 20126 Milan – Italy

b Department of Environmental Sciences, Università degli Studi di Milano-Bicocca, Piazza della Scienza, 1, 20126 Milan, Italy

The photochemistry of an organometallic complex can be investigated by means of excited state PESs explorations along relevant coordinates computed on the ground state PES1 or by means of Time-Dependent Density Functional Theory (TDDFT) geometry optimizations.2 The case of the CO photolysis of Fe2(S2C3H6)(CO)6, a model of the [FeFe] hydrogenases catalytic site in considered.3 Upon irradiation with near UV light, Fe2(S2C3H6)(CO)6 undergoes CO photolysis with the formation of the 32e- Fe2(S2C3H6)(CO)5 species and successively a solvent adduct.

One of the open question regarding this process is to understand if the photo-dissociated CO ligand is the apical or equatorial one. The picture that emerges the from excited state PESs explorations carried out along the Fe-C bond stretching coordinates change as a function of the functional adopted (BP86 and PBE0), while TDDFT geometry optimization picture is less influenced by the type of functional. [1] Dunietz, B. D.; Dreuw, A.; Head-Gordon, M.; J. Phys. Chem. B, 2003, 107, 5623-5629. [2] Bertini, L.; Greco, C.; De Gioia, L.; Fantucci, P.; J. Phys. Chem. A, 2009, 113, 5657-

5670. [3] Marhenke, J.; Pierri, A. E.; Lomotan, M.; Damon, P. L.; Ford, P. C.; Works, C. Inorg.

Chem. 2011, 50, 11850-11852.


65

STUDY OF THE SPECIATION OF THE [Cu(HGGG)(Py)] COMPL EX IN

WATER SOLUTION USING DFTB AND DFT APPROACHES

Maurizio Bruschia, Luca Bertini,b Vlasta Bonačić-Koutecký,c Luca De Gioia,b Roland Mitrić,d Giuseppe Zampella,b Claudio Greco,a Piercarlo Fantuccib

a Department of Environmental Science, University of Milano-Bicocca, Piazza della Scienza 1, I-20126 Milano, Italy.

b Department of Biotechnologies and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, I-20126 Milano, Italy.

c Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, D-12489 Berlin, Germany.

d Fachbereich Physik, Freie Universität zu Berlin, Arnimallee 14, D-14195 Berlin, Germany. DFTB and DFT methods have been employed as a part of a new computational protocol for the study of speciation of metal-peptide complexes hydrated in a sphere of water molecules, considering as an example, the Cu(II) complex [Cu(HG1G2G3)(Py)(W)] (H=histidine, G=glycine, Py=pyridine and W=H2O), which contains the species [Cu(HG1G2G3)] related to compounds formed by the interaction of the Cu2+ ion with the prion protein.1 The DFTB calculations were possible thanks to a careful parameterization of the atom-atom repulsive energy terms for Cu-H, Cu-C, Cu-N, and Cu-O. The speciation process is carried out by computing different DFTB steered molecular dynamics (SMD) trajectories, in which one or two selected ligands are dissociated, to form well defined penta- and tetra-coordinated different forms. The last frame of each trajectory is subjected to geometry optimization both at DFTB and DFT level, leading to different isomers. From the corresponding energy values a rank of relative stability of the isomers can be established. The computational protocol here developed is of general applicability to other metal-peptide systems and represents a new powerful tool for the study of speciation of metal-containing systems in water solution. For the Cu(II) complex investigated the results allow to conclude that in the presence of pyridine the lowest energy isomer is the five-coordinated form CuNHNG1NG2OG2NPy. To this conclusion converge, with substantial agreement, DFTB and DFT-TZVP results, the last including both 84 and 40 water molecules. This agreement represents a very encouraging result for a large scale application of our computational protocol in the study of speciation of other copper-peptide systems. [1] Bruschi, M.; Bertini, L.; Bonačić-Koutecký, V.; De Gioia, L.; Mitrić, R.; Zampella, G.; Greco, C.; Fantucci P. J. Phys Chem. B 2012, 116, 6250-6260.


66

ARE THE NONADIABATIC TRANSITION RATES TRANSFERABLE

AMONG DIFFERENT ENVIRONMENTS?

Valentina Cantatore, Giovanni Granucci, Maurizio Persico

Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via Risorgimento 35, 56126 Pisa

We want to investigate the transferability of the nonadiabatic transition rates in different environments when expressed as functions of few dynamical variables. As a test case, we choose the photoisomerization of both isomers (trans and cis) of

azobenzene excited in the n→ π*

band, because of our previously acquired experience with this problem [1]. As first hypothesis we have taken as independent dynamical parameters the energy difference between the two electronic states ∆E and the kinetic energy of the four atom of the CNNC azo-group Ek,4 (PNAD: Parametrized NonAdiabatic Dynamics). Figure 1 shows the

transition rates T(S1→ S0) obtained for single integration time steps in a swarm of about 200 trajectories starting from trans-azobenzene. To store

and retrieve the T(k→ l) data we distribute them in a grid according to the ∆E and Ek,4 variables. We tested the transferability of the transition rates to the case of a solvent of medium viscosity, modeled by integrating the trajectories by Langevin’s equation. The Langevin’s dynamics shows a considerably

slower decay with respect to vacuum in the case of the trans→ cis photo-isomerization (see Figure 3), while the rate is almost unaffected in the

cis→ trans case. In spite of this, by comparing the average transition rates obtained for each cell in the ∆E/Ek,4 grid we find essentially the same values (see figure 2). In the attempt to simplify and accelerate the nonadiabatic

1e-05

0.0001

0.001

0.01

0.1

1

10

1e-05 0.0001 0.001 0.01 0.1 1 10

Lang

evin

fs-1

vacuo fs-1

hopping ratesf(x)

1e-07

1e-06

1e-05

0.0001

0.001

0.01

0.1

1

10

0 0.5 1 1.5 2 2.5 3

tran

sitio

n ra

te, f

s-1

S0-S1 energy difference, eV

m.d. values

Figure 2

Figure 1


67

trajectory calculations, we used the transition rate data computed in vacuo to simulate the decay in the Langevin case. We applied a stochastic algorithm in order to represent the extreme variability of the transition rate data. At each step of the trajectory we pick at random a transition rate from the appropriate ∆E/Ek,4 cell in the grid. These tests show that our method is able to reproduce in a very good manner the differences in the decay times for simulations run in different environments (see Figure 3). The photo-isomerization quantum yields for

cis→ trans isomerization are almost unaffected by the solvent and are well reproduced by the PNAD dynamics. For

the trans→ cis case the solvent causes a rise in the quantum yields (from 0.33 to 0.37), a counterintuitive effect that was already observed and explained in simulations with an explicit solvent. Up to now we were not able to obtain the same effect by PNAD simulations. The reproduction of the quantum yield is a particularly hard test because the fate of a trajectory depends on fine details

concerning the geometry and nuclear momenta at the time of the hopping from the excited to the ground state. [1] Cusati T., Granucci G., Persico M. J. Am. Chem. Soc. 2011, 128, 194312.

0

0.2

0.4

0.6

0.8

1

0 500 1000 1500 2000

frac

tion

of tr

ajec

torie

s

time (fs)

S1 model dynamicsS1 PNAD vacuo

S1 mod. dyn. LangevinS1 PNAD Langevin

Figure 3


68

THEORETICAL ADSORPTION OF METHANE, HYDROGEN AND

CARBON DIOXIDE IN POROUS AROMATIC FRAMEWORKS (PAFs)

L. Canti, A. Fraccarollo, M. Cossi, L. Marchese

Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale “Amedeo Avogadro”, Viale T. Michel 11, 15121, Alessandria, Italy.

E-mail: [email protected] Porous aromatic frameworks (PAF) are synthetic materials with 3D structure of diamond where the sp3 carbon atoms are joined by short-to-long (poly)aromatic chains [1]. These materials haves some of the highest specific surface areas observed for organic microporous frameworks and are likely to be excellent adsorbents for methane, hydrogen and carbon dioxide. In the present work, the Grand Canonical Montecarlo (GCMC) technique was used to model this newly developed class of materials which are obtained from a diamond structure replacing each C-C covalent bond with phenyl rings or polyaromatic chains. Materials PAF-30n (n = 1,2,3,4), where n is the number of phenyl rings inserted in the C−C bonds, have been studied (Fig. 1) [2]. The ability of these materials to adsorb gases at different pressures and at different temperatures has also been investigated, along with their BET surface area. Ab initio calculations were performed at DFT level, with the 6-31G(d,p) and 6-311+G(d,p) basis sets, using Gaussian03(G03) package. The structural properties of PAF-30n models were estimated using the GEPOL procedure, implemented in G03 as part of the Polarizable Continuum Model of solvation. Methane, hydrogen and carbon dioxide adsorption isotherms were simulated using the Sorption module included in Materials Studio package, in a series of Grand Canonical Monte Carlo (GCMC) simulations. Simulations (Fig. 2) show that some members of the PAF family have great potential as methane and carbon dioxide adsorbents. These results are based on ideally crystalline materials and lower performances are expected in actual working conditions, but these materials are very promising candidates for many applications involving gas adsorption.

Fig.1. Top to bottom: aromatic building block, tridimensional structure of the unit cell, and skeletal volume defined as a collection of atomic spheres by the GEPOL procedure for the PAF-30n, n=1−4.


69

Fig.2 . Example of GCMC adsorption isotherms: methane in PAF-30n at 298K. The density of free gaseous methane (from EOS) is shown for comparison. The black square indicates the storage target proposed by DOE at 35 bar, 298 K. [1] T. Ben, H, Ren, S. Ma, D. Cao, J. Lan, X. Jing, W. Wang, et al. Angewandte Chemie.

2009, 48(50), 9457-60. [2] M. Cossi, G. Gatti, L. Canti, L. Tei, M. Errahali and L. Marchese., Langmuir 2012,

28(40), 14405-14.


70

THEORETICAL INVESTIGATIONS OF SrTi 1-XMXO3-δδδδ (M = Co, Ni, Cu)

DOPED-PEROVSKITE SYSTEMS: EFFECTS OF THE DOPING ON

THE FORMATION OXYGEN VACANCIES

Silvia Carlotto,a Andrea Vittadini,b Antonella Glisenti,a Marta Maria Natileb

a Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via F. Marzolo 1, 35131, Padova, Italy

b CNR-ISTM, Via F. Marzolo 1, 35131 Padova, Italy SrTiO3 is a prototype of ABO3 perovskite-type oxides, a class of materials with a wide range of technological applications, such as gas sensors, solid oxide fuel cells, electrochemical and memory devices and catalyst [1]. An important role in determining the properties of these materials is played by oxygen vacancies, whose formation is favoured by dopants. Thus, the material properties can in principle be tuned by a careful doping of the host. In this habit, accurate theoretical calculations can be useful in suggesting suitable strategies to manipulate and enhance the number of oxygen vacancies in this material to tune, for example, its catalytic properties [2]. We present a study where density functional theory (DFT) calculations are employed to study how the electronic structure of SrTiO3 is modified by the introduction of diluted (~6%) substitutional M dopants (M = Co, Ni and Cu). The effects of the doping on the stability of vacancies is also investigated, both in the bulk material and at the (001) surface. The influence of the theoretical approach (DFT vs. DFT+U) on the results is finally examined. Overall, our results show that doping has strong effects on the host material, and that these effects are sensitive to the dopant chemical identity. [1] The Chemical Physics of Solid Surfaces – Oxide Surfaces, edited by P. Woodruff

(Elsevier, Amsterdam, 2001). [2] Rodiguez, J. A.; Azad, S.; Wang, L. –Q.; Garcia, J.; Etxeberria, A.; Gonzalez, L. J. Chem.

Phys. 2003, 118, 6562-6571.


71

ASSESSMENT OF THE GEOMETRICAL CORRECTION FOR THE

BSSE IN DFT CALCULATIONS FOR MOLECULAR CRYSTALS

B. Civalleri, M. Alessio

Dipartimento di Chimica, Università di Torino, Via P. Giuria 7, 10125 Torino, Italy When using incomplete atom centered basis sets, the computed interaction energies in a supermolecular approach are subject to the basis set superposition error (BSSE). It arises from an unbalance basis set expansion of monomers with respect to the molecular adduct. The BSSE can give binding where there is none and prevent the use of small-to-medium size basis set (e.g. 6-31G(d)) which are still widely employed for large systems, as well as for solids. The removal of the spurious BSSE binding is also crucial to avoid artefact in the molecular geometry when dispersion corrections are included (e.g. DFT-D2). The BSSE is usually taken into account by using the well-known Boys-Bernardi counterpoise (BB-CP) correction [1]. However, it is limited to intermolecular BSSE and the correction of the potential energy surface is complicate. Recently, Kruse and Grimme [2] proposed a semi-empirical counterpoise-type correction in molecular systems which depends only on the molecular geometry and is denoted as geometrical counterpoise (gCP). It consists of an atom pair-wise potential that corrects for the inter- and intra-molecular BSSE in supermolecular HF or DFT calculations. In the present work, the gCP method has been extended to periodic systems and implemented in a development version of the CRYSTAL code [3]. Here we show preliminary results on the application of the gCP method to molecular crystals. Simple molecular solids (e.g. N2, CO2, CO, C6H6, ...) are used as test cases and comparison is done with the BB-CP results and large basis sets (e.g. QZVP). Results are encouraging but not as good as for the original set of molecular adducts used for setting up the empirical correction. This is likely due to the inadequacy of the fitted parameters to fully correct BSSE in molecular crystals. Furthermore, the inclusion of a dispersion correction to DFT shows that a recalibration of the method is needed to improve results. [1] Boys, S.; Bernardi, F. Mol. Phys. 1970, 19, 553. [2] Kruse, H.; Grimme, S. J. Chem. Phys. 2012, 136, 154101. [3] Dovesi, R.; et al. CRYSTAL09 User’s Manual, 2010, Torino.


72

AB INITIO MODELING OF METAL-ORGANIC FRAMEWORKS:

INSIGHTS ON STRUCTURE-PROPERTY RELATIONSHIPS

B. Civalleri,a E. Albanese,a L. Valenzano,b R. Orlandoa

a Dipartimento di Chimica, Università di Torino, Via Giuria 7, 10125 Torino, Italy b Department of Chemistry, MichiganTech University, Houghton, MI, USA

Metal-organic frameworks (MOFs) are a relatively new class of materials that combine inorganic moieties (a metal ion or a cluster), acting as connectors, with organic linkers to form a porous three-dimensional framework. The combination of different connectors and linkers makes MOFs very versatile materials with interesting and promising applications in many fields, namely: gas adsorption, storage and separation, catalysis and photocatalysis, gas sensors, nonlinear optics [1]. A better understanding of their properties is then important to guide tailoring and engineering of new MOFs with improved capabilities. In this respect, ab-initio modeling offers a useful tool to get new insight into the structure-property relationships of MOFs from an atomistic point of view. Here, we give an brief overview of our recent results on a throughout theoretical characterization and prediction of structural, electronic, vibrational, elastic and adsorption properties of various MOFs [2,3,4,5]. Among them: (i) adsorption of small molecules (e.g. CO, CO2) in open metal MOFs such as MOF-74(Mg,Ni,Zn) [2], Ni-BPB [3] and Ni-BTP. (ii) Electronic properties (i.e. band gap, refractive index, ...) of a set of selected MOFs [4,5]. For example, the semiconductor-like character of IRMOF-1 can be tuned by changing the organic linker or by its functionalization. Also, the role of metal ions will be highlighted for MOF-74(Mg,Ni,Zn). All results were obtained through a fully periodic ab-initio approach with the CRYSTAL program.[6] [1] Special issue: “Metal-Organic Frameworks”, Chem. Soc. Rev. 2009, 38, 1201. [2] Valenzano, L.; Civalleri, B.; Chavan, S. et al. J. Phys. Chem. C 2010, 114, 11185;

Valenzano, L.; Civalleri, B.; Sillar, K.; Sauer, J. J. Phys. Chem. C 2011, 115, 21777. [3] Albanese, E..; Civalleri, B.; et al. J. Mater. Chem. 2012, 22, 22592. [4] Civalleri, B.; Napoli, F.; Noel, Y.; Roetti, C. et al. CrystEngComm 2006, 8, 364 [5] Valenzano, L.; Civalleri, B.; Chavan, S.; Bordiga, S. et al. Chem. Mater. 2011, 23, 1700. [6] Dovesi, R.; et al. CRYSTAL09 User’s Manual, 2010, Torino.


73

AB INITIO SIMULATION OF SPECTROSCOPIC AND OPTICAL

PROPERTIES OF NOVEL POROUS GRAPHENE PHASES

M. De La Pierre,a P. Karamanis,b J. Baima,a R. Dovesia

a Dipartimento di Chimica, Università degli Studi di Torino, Italy b Institut Pluridisciplinaire de Recherche sur l’Environnement et les Matériaux,

Université de Pau et des Pays de l’Adour, France We present a detailed periodic ab initio quantum-mechanical simulation of two recently proposed systems, namely hydrogenated porous graphene (HPG) and biphenyl carbon (BPC), using hybrid HF-DFT functionals and all-electron Gaussian-type basis sets [1]. The equilibrium geometry, the vibrational spectrum (including IR intensities), the full set of components of the polarizability and hyperpolarizability tensors are provided, the latter evaluated through a Coupled-Perturbed KS/HF scheme. IR and Raman spectra for the two systems are quite different, and differ also from graphene, thus permitting their experimental identification. It is then shown that small defects inserted into the graphene sheet lead to finite values for the in-plane components of the static (hyper)polarizability tensors, spanning a relatively large range of values. By dehydrogenation of porous graphene into biphenyl carbon, a noteworthy enhancement of the non-linear optical properties through the static second dipole hyperpolarizability can be achieved. Vibrational contributions to the polarizability are negligible for both systems. [1] M. De La Pierre, P. Karamanis, J. Baima, R. Orlando, C. Pouchan, and R. Dovesi,

accepted for publication in J. Phys. Chem. C.


74

AB INITIO MÖSSBAUER ISOMER SHIFT AND QUADRUPOLE

SPLITTINGS OF 57Fe WITH CRYSTAL

S. Casassa, A. M. Ferrari

Dipartimento di Chimica, Università di Torino and NIS-Nanostructured Interfaces and Surfaces-Center of Excellence, Via P. Giuria 7, 10125, Torino, Italy

When a γ photon interacts with a nucleus a spin transition, from a lower to an higher spin status, can be promoted. The transition can be accompanied by three different effects, originated by interaction of the nucleus with both the electric and the magnetic field. The isotropic effect and the quadrupolar interaction, due to the isotropic and anisotropic contribution of the electric field respectively, has been calculated with the ab initio quantum-mechanic periodic CRYSTAL code [1] for 57Fe. Both the influence of the basis set and the Hamiltonian have been investigated. Comparison with experimental data and previous literature results [2] are presented and commented. The calibration of the isomer shift of 57Fe represents the starting point for detailed investigation of this nucleus in metallorganic compound. [1] R. Dovesi, V.R. Saunders, C. Roetti, R. Orlando, C.M. Zicovich-Wilson, F. Pascale, K.

Doll, N.M. Harrison, B. Civalleri, I.J. Bush I.J. et al., CRYSTAL09 User’s Manual (Universita` di Torino, Torino, 2010) [http://www.crystal.unito.it].

[2] U.D. Wdowik and K. Ruebenbauer, Phys. Rev. B 2007, 76, 155118.


75

DESIGN OF NOVEL WO 3-BASED MATERIALS WITH TAILORED

OPTICAL AND PHOTO-REDOX OR CATALYTIC PROPERTIES

Cristiana Di Valentin, Fenggong Wang, Massimo Rosa, Gianfranco Pacchioni

Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Cozzi 53, 20125 Milano

In this presentation we review some recent examples, based on density functional theory calculations, of different approaches to design novel WO3-based materials with peculiar photo-redox, optical or catalytic properties: doping, controlled defectivity or oxide clusters deposition on activated surfaces. Periodic calculation have been performed with hybrid functional methods and an atomic basis set approach, as implemented in the CRYSTAL code. Hybrid functionals provide a more accurate description of the semiconductors electronic structure (e.g. band gap values, spin localization) with respect to standard LDA or GGA functionals. The first example is doped-WO3 [1] for photocatalytic water splitting. Doping inorganic solids with impurity atoms is a consolidated method to modify their chemical and electronic properties. Since the position of the conduction and valence band edges of WO3 fits the oxidation potential for O2 evolution but not the reduction potential for H2 evolution, a positive shift of both edges would be highly beneficial for one-photon water splitting. Calculations indicate that such an effect can be obtained by W substitution with larger metal cations such as Hf [2]. The second examples is defective WO3-x which is well-known for its electrochromic properties above a certain degree of oxygen deficiency. The origin of the electrochromic effect in WO3 is, however, still an open issue. We propose [3] a rationalization based on a charge state variation of the oxygen vacancy defects and we also show that these present rather anisotropic properties. The third example is a catalytic system based on (WO3)3 clusters deposited on the rutile (110) TiO2 surface which is found to catalyze the formaldehyde polymerization reaction at very low temperatures. We propose [4] a novel radical reaction path with very low activation barriers which is triggered by the presence of extra electrons on the (WO3)3 clusters as induced by a defective TiO2 support. [1] F. Wang, C. Di Valentin, G. Pacchioni, J. Phys. Chem. C 2012, 116, 8901. [2] F. Wang, C. Di Valentin, G. Pacchioni, ChemCatChem 2012, 4, 476. [3] F. Wang, C. Di Valentin, G. Pacchioni, Phys. Rev. B 2011, 84, 073103. [4] C. Di Valentin, M. Rosa, G. Pacchioni, J. Am. Chem. Soc. 2012, ASAP.


76

COMPETITIVE SOLVATION OF K + BY C6H6 AND H2O IN THE

K+-(C6H6)n-(H2O)m (n=1-4; m= 1-6) AGGREGATES.

Noelia Faginas Lago,a M. Albertíb

a Dipartimento di Chimica, Università di Perugia, Perugia (Italy) b IQTCUB, DepartamentdeQuíımica Física,Universitat de Barcelona, Barcelona (Spain)

The competitive solvation of the potassium ion by benzene and water is investigated at molecular level by means of Molecular Dynamics simulations on the K+-(C6H6)n-(H2O)m (n=1-4; m=1-6) ionic aggregates. The preference of K+ to bind (C6H6) or (H2O) is investigated in the range of temperatures in which isomerization process are likely by adding water and benzene to the K+-(C6H6)n and K+-(H2O)m aggregates, respectively. Hydrogen bonds and the π-hydrogen bond, in spite of their weakness with respect to the K+-π and K+-(H2O) interactions, play an important role in stabilizing different isomers, thus favoring isomerization processes. Accordingly with experimental information it has been found that K+ bind preferably (C6H6) better than (H2O) and that the fragmentation of (C6H6) is only observed for aggregates containing four molecules of benzene

Fig.1 Two dimensional map of the probability density of the water molecules drown as a plane parallel to that of the aromatic ring for the K+-(C6H6)n-(H2O)m


77

COMPUTATIONAL APPROACHES EMPLOYED IN THE

SusFuelCat PROJECT

Francesco Ferrante, Nerina Armata, Remedios Cortese, Fabrizio Lo Celso,

Antonio Prestianni, Dario Duca

Dipartimento di Fisica e Chimica dell’Università, viale delle Scienze Ed. 17, I-90128 Palermo

Aim of the FP7 EU SusFuelCat project [1] is the biomass conversion for sustainable green–fuel production, to reduce the reliance of Europe on fossil fuel and to provide environmentally friendly energy. Aqueous phase reforming (APR) is one of the most competitive ways for the production of liquid and gaseous fuels from biomass. APR enables processing of wet biomass resources without energy intensive drying and additional hydrogen production from water by the water-gas-shift reaction. Catalysis technology is a key in APR. Hence, the project aims at a concentration of the European expertise in industry and academia in this area, and more specifically the synthesis, production, optimization and further know-how of hydrothermally stable carbon supported catalysts. Role of the group – from the Dipartimento di Fisica e Chimica dell’Università di Palermo – in the project concerns theoretical studies, in the field of the involved experimental project-systems. Model calculations will focus on local carbonaceous support properties, formation of the metal (Ni, Pt, Ru, Pd) supported nanostructures and specific metal-metal interactions within metallic or bimetallic (Pt-Ru) nano-clusters. Ab initio and/or DFT paradigms in the frame of cluster approaches will be used. A selection of catalyst prepared by experimental partners will be considered hence a selection of model catalysts will be performed. Effects of the reaction solvent (water) on the supported metal cluster will be studied also with the introduction of discrete water molecules. An integrated in silico approach will be performed on the kinetics vs. structural-results, regarding APR elementary events and reactions. In fact, the fully atomistic QM calculations and MD simulations utilized for the description of the structural characteristics of the carbonaceous supports and metal-containing catalysts will be employed as starting material for the whole characterization of the kinetic properties of the reactions in which the catalysts are involved. [1] SusFuelCat: Sustainable fuel production by aqueous phase reforming – understanding

catalysis and hydrothermal stability of carbon supported noble metals. GA: CP-IP 310490 http://cordis.europa.eu/projects/rcn/106702_en.html.


78

CHEMICAL REACTION BETWEEN AMINO-FUNCTIONALIZED

PORPHYRIN AND CYANURIC CHLORIDE ON SILVER:

A STM/DFT STUDY

Daniel Forrer,a Marco Di Marino,b Francesco Sedona,b Mauro Sambi,b

Andrea Vittadini,a Maurizio Casarinb

a Istituto di Scienze e Tecnologie Molecolari, CNR e b Dipartimento di Scienze Chimiche, Università di Padova

5,15-bis(4-aminophenyl)-10,20-diphenylporphyrin (TPP(NH2)2) reacts with cyanuric chloride (CC) on Ag(100) at room temperature, leading to the formation of 5,15-bis(4-cyanamidophenyl)-10,20-diphenylporphyrin (TPP(NHCN)2). The reaction product self-organize on the Ag(100) surface and forms two phases, which show largely different surface density. Density functional theory (DFT) calculations show that different intermolecular bond types stabilize the two phases. Indeed, in the sparser network molecules interact mainly through strong, directional hydrogen bonds, while in the denser phase weak, non-directional van der Waals interactions dominate. The cyanamide moiety exists in two forms related by a tauromerism. Interestingly, the each phase is composed by one single tautomer, while the other isomer forms the other phase. In fact, the sparser, h-bonded network promotes the formation of the cyanamide isomer, while in the denser packing the diimide moiety is the most stable.


79

MOLECULAR SIMULATION OF H 2 AND CH4 ADSORPTION

IN POROUS DIPEPTIDE CRYSTALS

Alberto Fraccarollo,a Maurizio Cossi,a Angiolina Comotti,b Leonardo Marchesea

a Dipartimento Scienze e Innovazione Tecnologica, Università Piemonte Orientale, Viale T. Michel 11, 15121 Alessandria, Italy

b Department of Materials Science, University of Milano Bicocca, Via R. Cozzi 53, 20125 Milano, Italy

The storage and separation of important gases, such as H2, N2, CH4, and CO2, is a challenging research field, due to the impending energy crisis and related global pollution that are dramatic issues today [1]

. The work presented here is the result of an investigation of the adsorption properties of eight different porous dipeptide crystals, which exhibit different pore networks. The adsorption isotherms of H2 and CH4 were simulated using Grand Canonical Monte Carlo method, following a previous simulation of CO2 and N2 with the same method [2]. The simulation were compared to experimental data where available [3]. In order to study the influence of the pore structure on the adsorption performance, pore size distributions, contour maps and snapshots were analysed and visualised. Finally, the accessible volume and surface area were calculated and compared to experimentally determined values, where available [4] to obtain an estimation of the quality of the experimental sample prior to adsorption measurements. [1] Wenliang Li, Jingping Zhang, Haichao Guo, Godefroid Gahungu, J. Phys. Chem. C

2011,115, 4935–4942. [2] Angiolina Comotti, Alberto Fraccarollo, et al., CrystEngComm, 2013, Advance Article,

DOI: 10.1039/c2ce26502h. [3] Angiolina Comotti, Silvia Bracco, Gaetano Distefano, Piero Sozzani, Chem. Commun.

2009, 284–286. [4] Dmitriy V. Soldatov, Igor L. Moudrakovski, Eugeny V. Grachev, John A. Ripmeester, J.

Am. Chem. Soc., 2006, 128, 6737-6744.


80

TOWARDS BULK THERMODYNAMICS VIA NONEQUILIBRIUM

METHODS: THE COMPRESSIBILITY FACTOR OF GASEOUS

METHANE AS CASE STUDY

Mirco Zerbetto, Diego Frezzato

Dipartimento di Scienze Chimiche, Università degli Studi di Padova, via Marzolo 1, I-35131 Padova

In the last decade, the so-called “Work Fluctuations Theorems” have been largely applied to build (both experimentally and numerically) free-energy profiles of molecular systems subjected to steered transformations along some coordinate(s) of interest [1]. In particular, the Jarzynski equality (JE) can be seen as the archetype of these tools. In the essence, the distribution of the amount of work, required to drive the (nonequilibrium) transformation according to a freely chosen protocol, is employed to compute the free-energy difference between initial and final (equilibrium) states; at the computational level, the efficiency of the JE lays in replacing a cumbersome calculus of configurational partition functions with simulation of few system’s trajectories in the steered transformations. To the best of our knowledge, up to now this nonequilibrium approach has been focused only on single-molecule studies (complex molecular systems or supra-molecular aggregates). Typical applications are encountered in biological contexts, e.g. probing the internal energetics in proteins and in protein-ligand complexes. Here we explore the applicability of the nonequilibrium tool to bulk homogeneous systems where the target is the determination of an equation of state given an estimation of the free-energy density. We adopt the gaseous methane as case study, aiming at the construction of the profile of the compressibility factor versus the gas pressure at fixed temperature. This goes through the evaluation of the pressure itself from the thermodynamic derivative of the Helmholtz free-energy. The latter is achieved by applying the JE with a “total morphing” schedule where the bulk state is let to “chemically grow up” from the ideal-gas state according to a prescribed protocol, which gradually turns on the intermolecular pair-interaction potential while the molecules explore the 3D-space via Markovian moves (a basic Monte Carlo “preferential sampling” with periodic boundary conditions propagator was employed). Preliminary calculations performed with a suitably parametrized Lennard-Jones pair-potential show a good agreement with experimental data. [1] Jarzynski, C. Annu. Rev. Condens. Matter Phys. 2011, 2, 329-351.


81

EFFECT OF TERMINAL OLIGO(ETHYLENE GLYCOL) ON THE

STRUCTURE OF ALKYLTHIOL SAMs: A MOLECULAR DYNAMICS

INVESTIGATION

Piero Gasparotto, Giulia Parisio, Alberta Ferrarini

Dipartimento di Scienze Chimiche, Università degli Studi di Padova, via Marzolo 1 – 35131 Padova (Italy)

Self-assembly of organosulfur compounds to form monolayers on metal surfaces is a spontaneous process, which has been widely exploited to modulate the interactions of surfaces and nanoparticles. The relationship between the chemical structure of self-assembled monolayers (SAMs), their organization and their properties has been extensively investigated by experimental and computational methods. However most studies have focussed on alkylthiol monolayers and much less is known on the organization of monolayers of different chemical nature. An important class of SAMs is represented by oligo(ethylene glycol) (OEG) terminated alkylthiols. First proposed by Prime and Whitesides in 1991 [1], these have become very popular because of some peculiarities, the most important of which is protein resistance. This behaviour has been the object of several experimental studies: some of them have pointed out the importance of single molecule properties, like the amphiphilic character of OEG and its conformational preferences, while others have stressed the role of the packing density, the presence of defects and the surface coverage. Here we present a Molecular Dynamics (MD) study of hydrated OEG-terminated alkylthiol monolayers adsorbed on Au(111). We have examined systems differing in the relative length of the alkyl and ether part of the chains and in the density of coverage of the gold surface and we have investigated the effects of these factors on the structural properties of the SAM. In particular we have focussed on interplay between conformation of the chains, organization of the monolayer and interaction with water. [1] Prime, K. L.; Whitesides, G. M. Science 1991, 252, 1164-1167.


82

QUANTITATIVE STRUCTURE-ACTIVITY RELATIONSHIPS

MODELLING AND PREDICTION OF ORGANIC POLLUTANTS

BEHAVIOUR IN THE ENVIRONMENT

Paola Gramatica, Stefano Cassani, Nicola Chirico, Simona Kovarich, Ester Papa

QSAR Research Unit in Environmental Chemistry and Ecotoxicology, Department of

Theoretical and Applied Sciences, University of Insubria, via J.H.Dunant 3, 2100 Varese. The predictive modelling approach, based on the development and validation of Quantitative Structure-Activity Relationships (QSARs), is highly useful in the screening of chemicals that are of recognized high concern in the environment, and also for the prioritization of compounds that haven’t experimental data or that have not yet been synthesized. Computational chemistry is the basis of QSAR models as the chemical structure must be carefully designed, minimized and translated in useful numerical information through various theoretical molecular descriptors. Some problems related to this preliminary and fundamental input for QSAR models will be addressed in this presentation [1]. The chemometric QSAR approach is mainly focused on the rigorous validation of the models by different validation tools to verify their predictivity, in particular for chemicals not used during the model development (external validation) [2]. Some examples of useful QSAR models, developed at University of Insubria, for the prediction of the atmospheric chemical reactivity of Volatile Organic Compounds [3], of the PBT behaviour [4] and of the soil sorption of pesticides [5], using the proprietary software QSARINS [6] will be presented. [1] Gramatica, P.; Cassani, S.; Roy, P.P.; Kovarich, S.; Yap, C.W.; Papa E. Mol. Inform.

2012, 31, 817-835. [2] Chirico, N.; Gramatica, P. J. Chem. Inf. Model. 2011, 51, 2320–2335 and 2012, 52,

2044-2058. [3] Roy, P.P.; Kovarich, S.; Gramatica. P. J. Comput. Chem. 2011, 32, 2386-2396. [4] Papa, E.; Gramatica, P. Green Chem. 2010, 12, 836-843. [5] Gramatica, P.; Giani, E.; Papa, E. J. Mol. Graph. Model, 2007, 25, 755-766. [6] Chirico, N.; Papa, E.; Kovarich, S.; Cassani, S.; Gramatica, P. QSARINS, software for

QSAR MLR model development and validation. 2012. University of Insubria, Varese, Italy. http://www.qsar.it


83

MODELLING OF THE ELECTROOPTICAL PROPERTIES OF

LIQUID CRYSTALS: THE MOLECULAR ORIGIN OF THE

ELECTROCLINIC EFFECT

Cristina Greco, Alberta Ferrarini

Department of Chemical Sciences, University of Padova, Italy Liquid crystals (LC) exhibit a variety of electrooptical phenomena, which are at the basis of different applications. An intriguing example is represented by the electroclinic (EC) effect, which is a tilt of the optical axis about an electric field, perpendicular to the optical axis itself. It was originally observed in macroscopically achiral smectic and nematic samples made of chiral molecules [1], but its molecular origin remained controversial. More recently, observation of the EC effect in a helically distorted sample of achiral molecules was interpreted as a sign of “top-down” induced deracemization [2]. Here we present a molecular model for the EC effect. By combining a proper account of the molecular and sample symmetry with a molecular level modeling we can provide a consistent description of the EC effect and quantitatively predict the material coefficients that govern this phenomenon. A detailed molecular level description is needed, in terms of molecular geometry, electric dipole and polarizability. In particular, a representation of the molecular polarizability with local resolution [3] is essential in the case of the helically distorted environment. We will present some examples and discuss the role of the molecular and phase chirality. Interestingly, we show that molecular chirality is not needed for the EC effect in the helical sample configuration, so contrasting the recent claims of a deracemization mechanism. [1] Li, Z.; Petschek, R. G.; Rosenblatt, C. Phys. Rev. Lett. 1989, 62, 796-799. [2] Basu, R.; Pendery, J. S.; Petschek, R.G.; Lemieux, R. P.; Rosenblatt, C. Phys. Rev. Lett.

2011, 107, 237804: 1-4. [3] Thole B.T. Chem. Phys. 1981, 59, 341-350.


84

REFINEMENT AND VALIDATION OF THE AMBER FORCE FIELD

FOR αααα, αααα DIALKYLATED PEPTIDES

Sonja Grubisic, a, b Giuseppe Brancato a , Vincenzo Barone a

a Scuola Normale Superiore, piazza dei Cavalieri 7, I-56126 Pisa, Italy. b Center for Chemistry, IHTM, University of Belgrade,

Njegoseva 12, 11001 Belgrade, Serbia. The popular biomolecular AMBER (ff99SB) force field has been extended and supplemented with new parameters for the simulations of peptides containing cyclic α,α dialkylated residues.1 Together with the recent set of nitroxide parameters2 this extension allows to treat the TOAC residue (TOAC, 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid) widely used as spin label in protein studies. All the conformational minima of the Ac-Ac6C-Nme (Ac=Acetyl, Ac6C=1-aminocyclohexaneacetic acid, Nme=Methylamino) and Ac-TOAC-Nme dipeptides have been examined in terms of geometry and relative energy stability by Quantum Mechanical (QM) computations employing an hybrid density functional (PBE0) and for an extended training set of conformers with various folds. We further advance simulation accuracy of Aib based peptides (Aib, alpha-aminoisobutyric acid) by improving relevant parameters of original AMBER99SB force field. Here, we used as reference data new high-level quantum-mechanical calculations with an added empirical dispersion correction, namely B3LYP-D. A very good agreement between QM and MM (molecular mechanics) data has been obtained in most of the investigated properties, including solvent effects. Molecular dynamics (MD) simulations of TOAC and Aib based polypeptides have been carried out to validate the resulting force field against available experimental data. The proposed force field accurately describes the conformation and dynamical behavior of the TOAC/Aib polypeptides in solvents with high and low polarity, in a good agreement with experimental and QM data. [1] Grubisic, S. ; Brancato, G; Pedone, A.; Barone, V. Phys. Chem. Chem. Phys. 2012, 14,

15308-15320. [2] Stendardo, E. ; Pedone, A. ; Cimino, P. ; Menziani, M. C. ; Crescenzi, O. ; Barone, V.

Phys. Chem. Chem. Phys. 2010, 12, 11697-11709.


85

DIELECTRIC NLO PROPERTIES OF POLYACETYLENE

R. Dovesi,a M. Ferrabone,a M. Ferrero,a,c B. Kirtman,b V. Lacivita,a R. Orlando,a M. Rératc

a Università di Torino, Italy b University of Santa Barbara, USA

c Université de Pau et des Pays de l’Adour, France In the past decades, nonlinear optics (NLO) has given great impetus to the development of laser, optical-communication and data-storage technologies. Meanwhile, engineering at nano-length scale has caught on with the detection of remarkable NLO properties by a number of nanomaterials, such as organic π-conjugated systems (polyenes, graphene and carbon nanotubes). Electronic and ionic contributions to the (hyper)polarizabilities of polyacetylene have been simulated[1,2] through the Coupled-Perturbed Hartree-Fock/Kohn-Sham computational scheme implemented in the CRYSTAL code[3]. Huge differences are observed on the longitudinal hyperpolarizability tensor component γL when different functionals are used: for the infinite model the ratio between LDA and HF becomes 1010[1]. On the basis of previous systematic comparisons including DFT, HF, Moller-Plesset (MP2) and coupled cluster results on finite chains, we can argue that the HF results are the most reliable for the infinite polymer. In most cases, the HF vibrational contribution is comparable to, or larger than the corresponding static electronic contribution[2]. The effect of the basis set is also explored, being particularly important for the non-periodic direction perpendicular to the polymer plane. [1] V. Lacivita, M. Rérat, R. Orlando, M. Ferrero and R. Dovesi J. Chem. Phys. 2012, 136,

114101. [2] V. Lacivita, M. Rérat, B. Kirtman, R. Orlando, M. Ferrabone and R. Dovesi J. Chem.

Phys. 2012, 137, 014103. [3] R. Dovesi, V. R. Saunders, C. Roetti, R. Orlando, C. M. Zicovich-Wilson, F. Pascale, B.

Civalleri, K. Doll, N. M. Harrison, I. J. Bush, P. D’Arco, and M. Llunell, CRYSTAL09 User’s Manual (University of Torino, Torino, 2009).


86

AB INITIO INVESTIGATION OF ELECTRONIC AND VIBRATION AL

CONTRIBUTIONS TO NONLINEAR DIELECTRIC PROPERTIES

OF ICE

Mahmoud, J. Baima, S. Casassa

Dipartimento di Chimica, Università di Torino and NIS-Nanostructured Interfaces and Surfaces-Center of Excellence, Via P. Giuria 7, 10125, Torino, Italy

The electronic and vibrational contribution to (hyper)polarizabilities for hexagonal ordinary ice has been investigated. Calculations have been carried out by the Finite Field Nuclear Relaxation (FF-NR) method [1], recently implemented in the CRYSTAL code, combined with the Coupled Perturbed Kohn-Sham (CPKS) method [2] at the B3LYP/[6-311Gdp2(f)] level for the electronic (hyper)polarizabilities (α , β, γ ) . Through a Berry phase approach static and electronic dielectric constants have been evaluate on different models of ice. The vibrational (ionic) contribution to the nonlinear optical properties have been calculated by the FF-NR method on the non periodic direction for slabs of ice with a space group Pna21 with increasing thickness, and by extrapolating these values, the vibrational contribution to (hyper)polarizabilities can be obtained for the periodic system. The correlation between the dielectric properties and the different structures of ice have been observed. [1] D. M. Bishop , M. Hasan, and B. Kirtman, J. Chem. Phys. 1995, 103, 4157. [2] M. Ferrero, M. Rérat, R. Orlando, and R. Dovesi, J. Comput. Chem. 2008, 29, 1450.


87

ELECTRONIC PROPERTIES OF H 2Pc AND CuPc FILMS:

AN EXPERIMENTAL AND THEORETICAL STUDY

Giulia Mangione,a Maurizio Casarin,a Roberto Verucchi,b Marco Nardib,c

a Dipartimento di Scienze Chimiche, Università di Padova, Via F. Marzolo 1, 35131 Padova, Italy

b Istituto dei Materiali per l’Elettronica ed il Magnetismo, sezione FBK di Trento, IMEM–CNR, Via alla Cascata 56/C – Povo, 38123, Italy

c Institut fur Physik, Humboldt-Universität zu Berlin, Newtonstrasse 15, 12489 Berlin, Germany

Films of phthalocyanine (H2Pc) and of its open-shell copper complex (CuPc) deposited on amorphous gold have been studied by combining the outcomes of several synchrotron based spectroscopic tools (X-ray photoelectron spectroscopy (XPS), UV photoelectron spectroscopy (UPS) and near-edge X-ray absorption fine structure spectroscopy (NEXAFS)) with the results of density functional theory (DFT) calculations. The assignment of experimental evidences has been guided by the results of DFT and time dependent DFT (TDDFT) numerical experiments carried out on the isolated molecules. With specific reference to CuPc NEXAFS data collected at the N K-edge, they have been assigned by using the open-shell TDDFT1 in the framework of the zeroth order regular approximation (ZORA) scalar relativistic approach. Besides the good agreement between theory and experiment, the combined use of NEXAFS data and DFT/TDDFT outcomes ultimately testified the significant ionic contribution characterizing the Cu–Pc interaction. [1] Wang, F.; Ziegler, T. Mol. Phys. 2004, 102, 2585-2595.


88

COHESIVE ENERGY OF MOLECULAR CRYSTALS THROUGH AB

INITIO POST-SCF HYBRID METHODS

Lorenzo Maschio,a Bartolomeo Civalleri,a Kamal Sharkas, b

Julien Toulouse, b Andreas Savin b

a Dipartimento di Chimica, and Centre of Excellence NIS (Nanostructured Interfaces and Surfaces), Università di Torino, via Giuria 5, I-10125 Torino (Italy)

b Laboratoire de Chimie Théorique, Université Pierre et Marie Curie and CNRS, 75005 Paris, France

E-mail: [email protected] A proper quantitative evaluation of intermolecular interaction energies is a prerequisite for an understanding of molecular aggregation modes in condensed phases, and hence for prediction and control of structural, thermodynamic, and physical properties of materials. Recently, quantum chemical methods have advanced to the point that cohesion energies of elementary molecular aggregates are more easily calculated than measured,[1] and, in general, molecular modeling is nowadays accepted and even widely encouraged as a complement, and in some cases even a substitute, of expensive experimental investigation. In this contribution we present the adaptation to periodic crystals of hybrid functionals combining Hartree-Fock exchange and second-order Møller-Plesset correlation with a semilocal exchange-correlation density functional.[2] Cohesive energies have been computed of a set of benchmark molecular crystals. DFT calculations with the CRYSTAL program (www.crystal.unito.it) are combined with the Local-MP2 method[3] implemented in CRYSCOR (www.cryscor.unito.it). Thanks to the use of density-fitting techniques for the fast evaluation of electron repulsion integrals and efficient parallelization,[4] the overall cost is manageable even for routine calculations, and significantly reduces the steep basis set dependence of the MP2 method alone. [1] (a) L. Maschio, B. Civalleri, P. Ugliengo, A. Gavezzotti, J Phys Chem A. 2011, 115(41);

(b) L. Maschio, D. Usvyat, B. Civalleri, CrystEngComm 2010, 12, 2429. [2] K. Sharkas, J. Toulouse, and A. Savin, J. Chem. Phys. 2011, 134, 064113. [3] C. Pisani, M. Schütz, S. Casassa, D. Usvyat, L. Maschio, M. Lorenz, and A. Erba, Phys.

Chem. Chem. Phys., 2012, 14, 7615. [4] (a) L. Maschio, D. Usvyat, F. R. Manby, S. Casassa, C. Pisani, and M. Schütz, Phys. Rev.

B 2007, 76, 075101; (b) L. Maschio and D. Usvyat, Phys. Rev. B 2008, 78, 073102; (c) L. Maschio, J. Chem. Theory Comput. 2011, 7, 2818.


89

AB INITIO ANALYTICAL INFRARED AND RAMAN INTENSITIES

FOR PERIODIC SYSTEMS THROUGH A CPHF/KS METHOD

Lorenzo Maschio,a Bernard Kirtman,b Michel Rérat,c

Roberto Orlando,a Roberto Dovesi a

a Dipartimento di Chimica, and Centre of Excellence NIS (Nanostructured Interfaces and Surfaces), Università di Torino, via Giuria 5, I-10125 Torino (Italy)

b Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA

c Equipe de Chimie Physique, Universitè de Pau, 64000 Pau, France E-mail: [email protected]

The theoretical simulation of the infrared (IR) and Raman vibrational spectra of crystalline materials can be an extremely powerful tool to support and complement the analysis of experimental data. In this connection it is of great importance not only to determine the position of the absorption peaks, i.e. the frequency of vibrational modes, but also the corresponding peak intensities. Periodic codes that allow one to compute IR or Raman intensities mainly adopt a density functional theory (DFT) CPKS approach together with a plane wave basis set calculation.[1] Although there are previous calculations in the literature that use atom-centered gaussian type orbitals (GTOs) as a basis set, implementations of IR intensities in general purpose electronic structure programs have been often limited to systems with one-dimensional periodicity,[2] and we are not aware of any implementation of Raman intensities for crystals adopting GTOs. In this contribution a fully analytical formulation will be presented that allows to compute the IR[3] and Raman intensities of crystalline periodic systems, as recently implemented in the CRYSTAL program, which uses a local Gaussian type basis set. The formalism is based on the combination of energy gradients of the integrals with a Coupled Perturbed Hartree-Fock/Kohn Sham (CPHF/KS) scheme [4] for the response of the density with respect to the electric field. It avoids numerical differentiation with respect to wave vectors and with respect to atomic coordinates. No perturbation equations for the atomic displacements need to be solved. Several tests have been carried out to verify numerical stability, consistency in one, two and three dimensions, and applicability to large unit cells. [1] S. Baroni, S. de Gironcoli, A. Dal Corso, P. Giannozzi, Rev. Mod. Phys. 2001, 73, 515. [2] A. Izmaylov and G. Scuseria, Phys. Rev. B 2008, 77, 165131. [3] L. Maschio, B. Kirtman, R. Orlando and M. Rérat, J. Chem. Phys. 2012, 137, 204113 [4] M. Ferrero; M. Rérat; B. Kirtman; R. Dovesi, J. Chem. Phys. 2008, 129, 244110.


90

COLLECTING AND VALIDATING LDHA CONFORMATIONS FOR

AN ENSEMBLE-BASED VIRTUAL SCREENING

Rosa Buonfiglio,a Maria Ferraro,a Federico Falchi,a Andrea Cavalli,a,b Matteo Masetti,a Maurizio Recanatinia

a Department of Pharmacy and Biotechnology, University of Bologna, Via Belmeloro 6, I-40126, Bologna.

b Department of Drug Discovery and Development, Istituto Italiano di Tecnologia, Via Morego 30, I-16163 Genova.

Human lactate dehydrogenase (LDH; EC 1.1.27) is a tetrameric enzyme responsible for the NADH dependent conversion of pyruvate to lactate. Five isoforms of the enzyme are possible basing on the assembly of two subunits, M and H (also known as A and B, respectively). The M4 homotetramer (or LDHA) is mainly found in tissues such as skeletal muscle and plays a key role in anaerobic metabolism [1]. The shift in energy production from oxidative phosphorylation to glycolysis (Warburg effect) is considered as an adaptive response of cancer cells to adverse hypoxic conditions typical of solid tumors. By catalyzing glycolytic metabolism, LDHA functions as tumor promoter, and for this reason in recent years this enzyme has emerged as an anticancer target [2]. The aim of this study is the development and validation of a computational protocol to be used in prospect for an ensemble-based Virtual Screening in search for novel LDHA inhibitors. In particular, 1) the large scale rearrangement of a 12 aa-long loop (which is known to be involved in substrate recognition) was sampled by means of the hybrid-REMD method [3], and 2) the ensemble of resulting conformations was analyzed by combining network and cluster analysis. Finally, 3) the best ranked conformations were validated by their ability to discriminate active compounds versus decoys generated by the DUD-E database [4], and active versus inactive compounds taken from the BindingDB [5]. [1]. Granchi, C.; Bertini, M.; Macchia, M.; Minutolo, F. Curr. Med. Chem. 2010, 17, 672-

697. [2] Le, A.; Cooper, C.M; Gouw, A.M.; Dinavahi, R.; Maitra, A.; Deck, L.M.; Royer, R.E.;

Vander Jagt, D.L.; Semenza, G.L.; Dang, C.V. Proc. Natl. Acad. Sci. USA 2010, 107, 2037-2042.

[3] Okur, A.; Wickstrom, L.; Layten, M.; Geney, R.; Song, K.; Hornak, V.; Simmerling C. J. Chem. Theory Comput. 2006, 2, 420–433.

[4] Huang, N.; Shoichet, B.K.; Irwin, J.J. J. Med. Chem. 2006, 49, 6789–6801. [5] Böde, C.; Kovács, I.A.; Szalayb, M.S.; Palotaib, R.; Korcsmárosb, T.; Csermely, P. FEBS

Lett. 2007, 581, 2776-2782.


91

MOLECULAR DYNAMICS OF MACROMOLECULAR SYSTEMS

IN LIPID BILAYERS

Roberta Galeazzi,a Luca Massaccesi, a Giovanna Mobbili, a Michela Pisanib

a Dipartimento di Scienze della Vita e dell’Ambiente, Università Politecnica delle Marche, via Brecce Bianche, Ancona, Italy

b S.I.M.A.U., Università Politecnica delle Marche, via Brecce Bianche, Ancona, Italy The accurate atomistic knowledge of the structure and dynamics of membranes has become in the last decade a new challenge due to its peculiar fluid character under physiological conditions, and to the lack of experimental data that are directly interpretable in terms of positions and motions of atoms.[1] Furthermore, the availability of high performance parallel computing has opened new ways to study lipid bilayers in atomic detail and thus full atom molecular dynamics simulations are able to compute a detailed picture of structure and dynamics of membranes [2]. In this study we presents our results in this field of research, focusing both to the characterization of membrane receptors in POPC bilayers and to the structural and dynamics picture of DOPC based mixed composition lipid bilayers.

[1] D.P. Tieleman, S.J. Marrink, H.J.C. Berendsen, Biochimica et Biophysica Acta 1997,

1331, 235–270. [2] S.E.Feller, “Computational Modeling of Membrane Bilayers”, Current Topics in

Membrane, Volume 60, 2008, Elsevier edition. .


92

THE LIPID BILAYER PERMEABILITY OF MOLECULAR SOLUTES :

BEYOND THE STANDARD SOLUBILITY-DIFFUSION MODEL

Giulia Parisio, Alberta Ferrarini

Dipartimento di Scienze Chimiche, Università degli Studi di Padova, via Marzolo 1 – 35131 Padova (Italy)

Besides active and mediated transport processes, small solutes and drug-like molecules can permeate the lipid matrix of biological membranes by a diffusion process driven by a concentration gradient between the water regions at the two membrane sides. The solubility-diffusion (SD) model originally proposed in 1974 relates the membrane permeability coefficient of a solute to its local partition and diffusion coefficient in the heterogeneous environment of the lipid bilayer.[1] In 1994 a computational method based on this model was proposed, which has become the standard approach for the calculation of permeability coefficients from Molecular Dynamics simulations.[2] Intrinsic to this approach is the reduction of permeation to an effective translational process, where any other degree of freedom of the permeant molecule is assumed to be irrelevant. Here we present a revision of the SD model of membrane permeability and propose a more general approach, which goes beyond the usual approximations. The theory is recast in the general framework of a roto-translational Fokker-Planck equation, and the classical SD expression for permeability is recovered when the permeation rate is determined by solute translation. A solution of the problem is achieved by describing the global kinetics of translocation in terms of transitions between adjacent free energy minima.[3] The expression for the permeability coefficient, in terms of the rates of the transitions along all the possible translocation paths, is rationalized within discrete path sampling theory.[4] Selected examples illustrate the multi-dimensional approach compared to the standard mono-dimensional approximation. [1] Diamond, J. M.; Szabo, G.; Katz, Y. J. Membr. Biol. 1974, 17, 148-152. [2] Marrink, S.-J.; Berendsen, H.J.C. J. Phys. Chem. 1994, 98, 4155-4168. [3] Parisio, G.; Sperotto, M. M.; Ferrarini, A. J. Am. Chem. Soc. 2012, 134, 12198-12208. [4] Wales, D. J. Mol. Phys. 2002, 100, 3285-3305.


93

SMOOTH FILLING OF THE SOLVENT-EXCLUDING VOLUME

WITH SPHERES

Christian Silvio Pomelli

Dipartimento di Farmacia – Università di Pisa, Via Bonanno 33, 56126 Pisa, Italy. Email:[email protected]

The solvent-excluding volume is the portion of space outside the van der Walls volume that is inaccessible by a spherical solvent probe. Thus volume is usually described using MSDOT [1] or GEPOL [2] algorithms. However both are unable to produce a continuous and differentiable description of the solvent-excluding volume and surface in terms of a collection of simple geometrical objects. This fact leads to numerical artefacts and catastrophes when we deal with non-rigid molecules (like in automated geometry optimization procedures). The method proposed in this contribution uses a different strategy based on:

The decomposition of the solvent-excluding volume in contributions related to pairs and triples of atoms [3]. The filling of these contributions with fixed radii auxiliary (non-atomic) spheres. A smoothly disposal of the auxiliary spheres that are not longer useful. The resulting set of auxiliary spheres is continuous and differentiable with respect the molecular geometry.

[1] M. L. Connolly, Science 1983, 221, 709–713. [2] J. L. Pascual-Ahuir and E. Silla J. Comp. Chem. 1990, 11, 1047-1060. [3] C.S. Pomelli and J. Tomasi J. Comp. Chem. 1998, 19, 1758-1776.


94

THEORETICAL STUDY OF THE PHOTOIONIZATION

CROSS SECTIONS OF METALLOCENES

P. Decleva, A. Ponzi

Dipartimento di Scienze Chimiche, Università di Trieste, via L. Giorgieri 1, 34127 Trieste, Italy

Strong oscillations in molecular photoemission cross sections, which persist up to hundreds of eV above threshold, have been first detected in C60, both in the solid state and gas phase. In the course of a theoretical investigation into photoemission from transition metal sandwiches, the same phenomenon has been uncovered in Magnesium Cyclopentadienyl (MgCp2) [1]. While it was assumed that photoionization profiles were essentially unstructured beyond some 100 eV above threshold, there is mounting evidence of notable structures which persist at high energies. The present work concerns the study of high energy structures in the photoionization of a series of metallocenes. The simulation approach, based on an accurate solution of the scattering problem in a Density Functional framework, provides excellent reproduction of the MgCp2 features. The computational approach utilizes a discretization of both bound and continuum functions in a multicenter basis of B-spline functions times spherical harmonics [2, 3]. The two outermost valence ionizations of MgCp2, HOMO and HOMO-1, corresponding to the in-phase and out-of-phase combinations of the highest p orbitals of the cyclopentadienyl rings, have been studied. The results obtained are compared to the analogous results for MgCp*2 and BeCp*2. The theoretical data show that the features of photoionization cross sections are dependent on the electronic effects (the presence of methyl groups determines different cross section profiles for MgCp and MgCp*2) and on the structural effects, related in our study to the different values of the metal – cyclopentadienyl ring distance. It appears that long range oscillations in molecular photoemission cross sections are a general phenomenon, which can convey important information on the geometric and electronic structure of the target. [1] Decleva, P.; Fronzoni, G.; Stener, M.; De Simone, M.; Coreno, M.; Green, J.C.; Hazari,

N.; Plekan, O. J. Chem. Phys. 2005, 122, 234301 [2] Stener, M.; Fronzoni, G.; Decleva, P. J. Chem. Phys. 2005, 122, 234301. [3] Bachau, H.; Cormier, E.; Decleva, P.; Hansen, J. E.; Martin, F. Rep. Prog. Phys. 2001, 64,

1815.


95

THE SOFT X-RAY ABSORPTION SPECTRUM

OF THE ALLYL FREE RADICAL

M. Alagia,a E. Bodo,b P. Decleva,c S. Falcinelli,d A. Ponzi,c

R. Richter,e S. Stranges a,b

a IOM-CNR, Laboratorio TASC, 34149 Basovizza, Trieste, Italy b Dipartimento di Chimica, Università degli studi di Roma “La Sapienza”,

piazzale Aldo Moro 5, 00185 Roma, Italy c Dipartimento di Scienze Chimiche, Università di Trieste,

via L. Giorgieri 1, 34127 Trieste, Italy d Dipartimento di Ingegneria Civile ed Ambientale, Università degli Studi di Perugia,

via G. Duranti 93, 06125 Perugia, Italy e Elettra-Sincrotrone Trieste, Area Science Park, 34149 Basovizza, Trieste, Italy

The allyl radical is the simplest p-conjugated electron system in organic chemistry. This molecule is presently one of the better understood polyatomic hydrocarbon radicals owing to its role as a model system to study chemical dynamics of radicals. [1] The present work is therefore aiming at reporting the first XAS of this radical and providing a detailed spectral assignment by means of a joint experimental and theoretical investigation. A supersonic He seeded beam of hyperthermal allyl radicals was crossed by a high resolution synchrotron radiation (SR) in the focus of a 3D ion momentum imaging time-of-flight (TOF) spectrometer to investigate the soft X-ray absorption and fragmentation processes. The XAS, recorded as Total-Ion-Yield (TIY), is dominated by C1s electron excitations from either the central carbon atom, CC, or the two terminal carbon atoms, CT, to the frontier orbitals, the semi-occupied-molecular-orbital (SOMO) and the lowest-unoccupied-molecular-orbital (LUMO). The number of transitions and their excitation energies and oscillator strengths are properly described by ab initio calculations performed at the CASSCF level. The failure of the one electron description of the XAS of the open shell radical and the required MCSCF approach emphasized the importance of the multi-reference nature of the corehole states of the allyl molecule. The lowest lying core excitation of the allyl radical displays a rich vibrational structure with sharp features in the experimental XAS. In order to analyze these spectral features, we have used the method FC-Classes, developed by Santoro at al. [2], to compute the vibronic structure of the optical transition. The main features of this vibrational structure have been explained in terms of excitation of the CH2 twist mode and the stretching of the two C–H bonds of this group. [1] Fischer, I.; Chen, P.; J. Phys. Chem. A, 2002, 106, 4291. [2] Santoro, F.; Improta, R.; Lami, A.; Bloino, J.; Barone, V. J. Chem. Phys., 2007, 126,

084509.


96

BENCHMARKING PERIODIC DISPERSION-CORRECTED

DFT CALCULATIONS FOR THE PREDICTION OF

MOLECULAR CRYSTAL POLYMORPHISM


Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia,

Via G. Campi 183, 41125 Modena, Italy Periodic Density Functional Theory (DFT) calculations employing the PBE, PBE0 and B3LYP functionals coupled with different dispersion-correction schemes (-D and –TS) have been applied to the para-diiodobenzene (p-DIB) molecular crystal in order to determine how they perform in reproducing the energetic and crystal geometry of its two well known polymorphs. Our results [1] showed that, when properly corrected, DFT calculations successfully predict the relative stability of the α (Fig.1) and β phases at zero temperature, in good agreement with Diffusion Monte-Carlo (DMC) calculations [2]. Among the two dispersion corrections employed, the recently proposed Tkatchenko and Scheffler (TS) scheme [3] performs much better than the original Grimme scheme (D) [4]. This is imputable to the accurate nonempirical method used to obtain the dispersion coefficients in the former approach. We are currently benchmarking the TS scheme also against a polar system, such as the oxalyl dihydrazide (Fig.2). This simple molecule gives rise to five different phases, in which the competition of intermolecular H-bond and dispersive interactions makes the prediction of the relative stability very challenging. The TS scheme leads to a nice agreement with experiment both for structures and thermodynamics. The TS and other analogous models for dispersion-correction are still not commonly used in computational chemistry but the results reported in literature denote the accuracy of such methods to describe long-range interactions. In our opinion, they can play a fundamental role to better understand the chemical and physical nature of weak interactions – not only in the field of molecular crystals – opening a new era for the design and the prediction of increasingly complex systems, as requested from the market.


97

[1] Pedone A.; Presti D.; Menziani M.C.; Chem. Phys. Lett. 2012, 541, 12-15. [2] Hongo K.; Watson M. A.; Sànchez-Carrera R. S.; Iitaka T.; Aspuru-Guzik A.; J. Phys.

Chem. Lett. 2010, 1, 1789. [3] Tkatchenko A.; Scheffler M.; Phys. Rev. Lett. 2009, 102, 073005. [4] Grimme S.; J. Comput. Chem. 2006, 27, 1787.


98

FROM PHENYL CHLORIDES TO αααα,n-DIDEHYDROTOLUENES

(αααα,n-DHTs) VIA PHENYL CATIONS. A CASSCF INVESTIGATION

Davide Ravelli, Stefano Protti, Maurizio Fagnoni, Angelo Albini§

PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy. Fax: +39 0382 987323; Tel: +39 0382 987316

E-mail:[email protected], website: www.unipv.it/photochem We recently reported that irradiation of the three isomeric (n-chlorobenzyl)trimethylsilanes in methanol-water opened a novel access (by a double elimination process) to the corresponding didehydrotoluenes (α,n-DHTs; see Scheme, left part).[1] Only the α,3-DHTs were previously generated in solution through the Myers-Saito protocol (the cycloaromatization of enyne-allenes; see Scheme, right part). This finding prompted the present computational study aimed at rationalizing the pathways involved in our approach.[2] The work revealed that efficient Inter System Crossing (Conical Intersection located) leads to the lowest-lying triplet state of the silanes that fragments to give the corresponding triplet aryl cations. Delocalization of the positive charge on the benzene ring plays a key role in the desilylation of these cations. In the case of para- and ortho- isomers, these have a radical/radical cation character and desilylate directly to yield the corresponding DHTs likewise in the triplet state (whereas desilylation has found to be not favored in the corresponding singlets). On the other hand, the meta-phenyl cation has a radical/radical cation structure in both spin states and thus has available two potential accesses to the different spin states of the corresponding DHT. [1] Protti, S.; Ravelli, D.; Mannucci, B.; Albini, A.; Fagnoni, M. Angew. Chem. Int. Ed. 2012,

51, 8577-8580. [2] Ravelli, D.; Protti, S.; Fagnoni, M.; Albini, A. submitted.

§ S.P. acknowledges MIUR, Rome (FIRB-2008 RBFR08J78Q) for financial support. This work has been supported by the Fondazione Cariplo (grant no. 2011-1839). This work was funded by the CINECA Supercomputer Center, with computer time granted by ISCRA COMPDHT (HP10CZEHG6) project.

Cl

CH2SiMe3

hν

ProticSolvent

CH2SiMe3

-SiMe3+

CH2

.

.CH2

∆(hν)

New approach Classical approach

+..

-Cl-

αααα,n-DHT


99

ELECTRONIC AND EPR SPECTRA OF THE SPECIES INVOLVED IN

[W 10O32]4- PHOTOCATALYSIS. A RELATIVISTIC

DFT INVESTIGATION

Davide Ravelli,a Daniele Dondi,a Maurizio Fagnoni, a Angelo Albini,a Alessandro Bagnob §

a PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy. Fax: +39 0382 987323; Tel: +39 0382 987316.

E-mail: [email protected], website: www.unipv.it/photochem b Department of Chemistry, University of Padova,

via Marzolo 1, 35131 Padova, Italy. The usefulness and versatility of polyoxometalates (POMs) in many areas of chemistry is widely recognized in the literature. POMs are routinely characterized by spectroscopic techniques such as NMR and IR; robust computational methods have been developed for the prediction of these spectra, and the electronic structure of these species has also been extensively investigated. Conversely, their electronic and EPR spectra are comparatively less understood and studied. This is relevant not only for their characterization by UV-Vis spectroscopy, but – most importantly – also for understanding their photoreactivity. In a recent work, [1] we showed that the prediction of the UV spectrum of POMs requires the inclusion of a solvation model and relativistic effects. GGA functionals are not suitable for such calculations, but hybrid functionals allow for a reliable calculation of transition energies and oscillator strengths, albeit at a much higher computational cost. In practice, it is found that a small number of hybrids, such as PBE0, provide optimal results. Overall such calculations turned out to be quite demanding; nevertheless, the problem is partly alleviated by the use of a frozen-core basis set. On this basis, we have undertaken an investigation of the electronic spectra of [W10O32]

4- (see Figure), its mono- [W10O32]

5- and bi-reduced forms [W10O32]6,

by relativistic DFT calculations; we have also modeled the EPR properties of [W10O32]

5- and its protonated forms. The study has led to a sound understanding of the involved transitions and the EPR spectra thereof, as well as predictions concerning NMR spectra. [2] [1] Ravelli, D.; Dondi, D.; Fagnoni, M.; Albini, A.; Bagno, A. J. Comput. Chem. 2011, 32,

2983-2987. [2] Ravelli, D.; Dondi, D.; Fagnoni, M.; Albini, A.; Bagno, A. Phys Chem. Chem. Phys.,

DOI: 10.1039/C2CP43950F.


100

NITROGEN AND CARBON K-EDGE NEXAFS SPECTRA OF MODEL

SYSTEMS FOR C5H5N ON Si(100) : A DFT SIMULATION

M. Romeo, G. Balducci, M. Stener, G. Fronzoni

Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Trieste,

Via L. Giorgieri 1, I-34127 – TRIESTE Adsorption of organic molecules on semiconductor surfaces has been attracting a growing attention for its importance in emerging technologies. Fundamental research on the covalent bonding of molecules with the surface can provide useful information on the organic/semiconductor interface. The NEXAFS spectroscopy [1] represents a powerful technique to investigate the orientation and geometry of molecules adsorbed on surfaces and is widely used to characterize adsorbate structures, often in concert with theoretical calculations [2]. The computational simulation of NEXAFS spectra of such systems represents a significant challenge both for a proper modelling of the adsorbate as well as for the size of the system itself, which needs theoretical methods capable to fulfill requirements of accuracy and computational economy. Here we present a DFT-TS [3,4] simulation of the NEXAFS spectra of pyridine adsorbed on a regular Si (100) – 2x2 surface by considering several adsorption models [5,6].

The models have been previously optimized through periodic calculations performed with the Quantum Espresso code, then suitable finite clusters have been cutted out from the optimized periodic structures and used for the simulation of the angle resolved NEXAFS spectra [7] of the adsorbed molecule by employing traditional molecular DFT techniques through the use of the ADF code. The results show a good match with the experimental spectra and this highlight the fact that the calculated polarized spectra can provide important informations on specific details of the adsorbtion geometries and that the methodology employed is reliable to describe the K-shell spectra of finite models of such solid state problems.


101

[1] J.Stöhr – NEXAFS Spectroscopy, Springer – Verlag, 1992 [2] G. Fronzoni, G. Balducci, R. De Francesco, M. Romeo and M. Stener, J. Phys. Chem. C

2012, 116 (35), 18910–18919. [3] John C. Slater – Advances in Quantum Chemistry, vol.6, pp. 1-92, Academic Press New

York · London, 1972. [4] David A. Liberman – Physical Review B, Third Series, vol. 62, n. 11, pp. 6851-6853, 15

September, 2000-I. [5] R. Coustel, N. and Witkowski, J. Phys. Chem. C 2008, 112, 14102–14107. [6] R. Coustel, N. Witkowski et al., Phys. Rev. B 2012, 85, 035323. [7] ADF External Utility®, a Fortran implementation to compute angle-resolved spectra from

ADF®, 2011 – source: www.archivemr.cz.cc


102

COARSE-GRAINED MD SIMULATIONS OF THE MESOMORPHIC

BEHAVIOUR OF 1-HEXADECYL-3-METHYLIMIDAZOLIUM

NITRATE

G. Saielli,a Y. Ji,b R. Shi,b G. A. Voth,c Y. Wangb

a ITM-CNR, Unità di Padova, Via Marzolo, 1 – 35131 Padova. b ITP-CAS, 55 E. Zhongguancun Rd., Beijing, China

cDepartment of Chemistry, 5735 S. Ellis Av., Chicago – IL (USA) Ionic Liquid crystals (ILCs) are a new class of materials composed of typical cation-anion combinations as usually found in ionic liquids (Ils), but exhibiting mesomorphism similarly to liquid crystals (LCs). The prototypes of such systems are 1-alkyl-3-methylimidazolium salts with various anions, such as Cl-, Br-, BF4

-, NO3- and alkyl chains of at least 14 carbon atoms [1].

In the present work we have used MD simulations to characterize the phase behavior of a coarse-grained force-field (CG-FF) model initially developed for 1-alkyl-3-methylimidazolium nitrates [2], that is systems with an alkyl chain of few carbon atoms. Moreover, only the isotropic liquid phase (the only one exhibited by the short chain imidazolium Ils, besides the crystal phase) was considered in the parameterization of the CG-FF model. For [C16mim][NO3] the ionic smectic phase has been indentified between 500 and 560 K [3]. We have characterized the structure and order parameters of the three phases observed, the crystal phase, the smectic A phase and the isotropic phase and compared with experimental data. Moreover, we have analyzed in detail the dynamics of cations and anions in the SmA phase and compared the results with the known behavior of pure LCs, LCs mixtures, which may share with ILCs an alternation of layers, and lyotropic liquid crystals which also share with ILCs a layered lamellar phase with alternating hydrophobic and charged regions [4]. Finally we have investigated the effect of the chain length on the relative weight of electrostatic vs van der Waals interactions through a properly defined heterogeneity order parameter (HOP) finding a discontinuity for C14 carbon chains, in remarkable agreement with the experimental observations of the appearance of a LC phase in imidazolium salts [5]. [1] Bradley,A.E.; Hardacre, C.; Holbrey, J.D.; Johnston, S.; McMath, S.E.J.;

Nieuwenhuyzen, M. Chem. Mater. 2000, 14, 629. [2] Wang, Y.; Feng, S.; Voth, G.A. J. Chem. Theory Comput. 2009, 5, 1091. [3] Saielli, G. Soft Matter 2012, 8, 10279. [4] Saielli, G.; Voth, G.A.; Wang, Y. submitted [5] Ji, Y.; Shi, R.; Wang, Y.; Saielli, G. J. Phys. Chem. B 2013, 117, on-line.


103

RELATIVISTIC DFT CALCULATIONS OF XENON NMR

PARAMETERS IN VAN DER WAALS SYSTEMS

G. Saielli,a A. Bagnob

a ITM-CNR, Unità di Padova, Via Marzolo, 1 – 35131 Padova. b Dipartimento di Scienze Chimiche, Via Marzolo, 1 – 35131 Padova.

Relativistic DFT methods have proven to be a valuable aid in the prediction and interpretation of NMR data of heavy nuclei. In this contribution we will discuss two recent results concerning the well-known NMR probe 129Xe where weak non-covalent interactions played a fundamental role. The first example is that of xenon encapsulated in a cryptophane, 1, which undergoes a dramatic deshielding upon permetallation of the cryptophane, 2, see Figure 1a). The relative ∆δexp for 129Xe inside the cryptophane, is 277 ppm. Relativistic ZORA-DFT calculations have allowed to disentangle the various contributions to the chemical shift variation due to solvent, charge redistribution and spin-orbit coupling and the calculated ∆δcalc of 281 ppm, is in remarkable agreement with the experiments. The second example concerns the spin-spin coupling between unbound spins, that is van der Waals complexes. ZORA-DFT calculations of the coupling constant between 129Xe and 1H of pentane, in structures obtained from snapshots of a classical MD simulation (see Figure 1b) of a xenon-pentane mixture, predicted the existence of an average through-space spin-spin coupling Jcalc(

129Xe,1H) of −3.2 Hz. This has been confirmed by SQUID NMR experiments, Jexp(

129Xe,1H) = −2.7 ± 0.6.

a) b) [2] Bagno, A.; Saielli, G. Chem. Eur. J. 2012, 18, 7341-7345. [1] Ledbetter, M.; Saielli, G.; Bagno, A.; Tran, N.; Romalis, M. Proc. Natl. Acad. Sci. USA

2012, 109, 12393-12397.


104

ORBITAL RELAXED DENSITY MATRIX AT LOCAL MP2 LEVEL

FOR PERIODIC SYSTEMS: FORMAL ASPECTS AND

IMPLEMENTATION

Simone Salustro, Lorenzo Maschio

Dipartimento di Chimica, Università degli Studi di Torino, via P. Giuria 5, I-10125 Torino (Italy)

In this poster an orbital relaxed density matrix formalism for periodic systems will be presented. The generic quantum mechanical wavefunction is a very huge object that gives us, with respect of its dimension, just few fragments of information about the system of interest. Nevertheless, using the wavefunction itself as starting point, it is possible to define a simpler object that leads to the same information: the density matrix. Treating the electron correlation as a perturbation of the Hartree-Fock description, its effects can be taken into account. CRYSCOR[1] is an ab initio software capable to describe crystalline solids at a correlated level, exploiting the HF wavefunction provided by CRYSTAL[2]. In particular, CRYSCOR implements the MP2 post-HF method within the Saebø-Pulay local[3] approach. Since the MP2 method is not a variational theory, Lagrangian techniques[4], that have been quite recently developed for molecules[5], must be used in order to obtain the expression of the correction to the HF density matrix. [1] Pisani, C.; Schütz, M.; Casassa, S.; Usvyat, D.; Maschio, L.; Lorenz, M.; Erba, A., Phys.

Chem. Chem. Phys., 2012, 14, 7615. [2] Dovesi, R.; Orlando, R.; Civalleri, B.; Roetti, C.; Saunders, V.R.; Zicovich-Wilson, C.M.,

Z. Kristallogr. 2005, 220, 571–573. [3] Pulay, P.; Saebø S.; Theor. Chim. Acta 1986, 69, 357. [4] Usvyat, D.; Schütz, M. J. Phys.: Conf. Ser. 2008, 117, 012027. [5] Helgaker, T.; Jørgensen, P.; Olsen, J. Molecular Electronic-Structure Theory, Wiley,

2000.


105

DEVELOPMENT OF A RELIABLE FORCE FIELD FOR CLASSICAL

MD SIMULATIONS IN ALUMINOSILICATES, ENABLING

FAST PARALLEL COMPUTATIONS

Andrea Gabrieli, Marco Sant, Pierfranco Demontis, Giuseppe B. Suffritti

Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, via Vienna 2, 07100 Sassari, Italy, email: [email protected]

The development of a new force field for fast molecular dynamics simulations in flexible aluminosilicates is presented [1]. This force field is in CHARMM functional form. As initial guess, the parameters are taken from previous works of both our group [2] and other authors [3], which are subsequently optimized by comparison with ab-initio data and experimental vibrational spectra, see Fig. 1. We validated the obtained force field checking its ability to reproduce the crystallographic structures of silicalite and zeolites Na A, Ca A, Na Y, and Na X.

Figure 1. IR spectra for silicalite: experimental [2] (dots), classical MD (dashes), ab-initio (line).

This new force field can be exploited within the most widespread computational packages, allowing the execution of large-scale simulations in a parallel environment. [1] Gabrieli, A. ; Sant, M. ; Demontis, P. ; Suffritti, G. B. J. Phys. Chem. C 2013, 117, 503-

509. [2] Demontis, P.; Suffritti, G. B.; Bordiga, S.; Buzzoni, R. J. Chem. Soc., Faraday Trans.

1995, 91, 525-533. [3] Nicholas, J. B.; Hopfinger, A. J.; Trouw, F. R.; Iton, L. E. J. Am. Chem. Soc. 1991, 113,

4792-4800.


106

A GENERAL ALL-COORDINATES QUANTUM-DYNAMICAL

APPROACH FOR DESCRIBING THE VIBRONIC LINESHAPE OF

ELECTRONIC CIRCULAR DICHROISM SPECTRA

IN EXCITON-COUPLED DIMERS

Fabrizio Santoro

Consiglio Nazionale delle Ricerche – CNR, Istituto di Chimica dei Composti Organo Metallici (ICCOM-CNR), UOS di Pisa, Area della Ricerca,

Via G. Moruzzi 1, I-56124 Pisa, Italy In this contribution we present a computational approach [1] to simulate the vibronic lineshapes of absorption and ECD spectra in exciton-coupled dimers [2]. Our method is based on a time-dependent expression of the spectra [3] that are computed though the quantum dynamics of suitable wave packets moving on coupled diabatic states localized on the monomers; it is general and straightforwardly applicable when the electronic potential energy surfaces of the monomer excitation can be described within harmonic approximation [1]. At variance with previous theoretical treatments [4, 5], our method allows to include the effect of all the vibrational modes of the system, accounting for geometry displacements, frequency changes and normal-modes (Duschinsky) mixing. This is possible exploiting a hierarchical representation of the Hamiltonian in blocks [6], defined so that few blocks (few coordinates) describe accurately the short-time dynamics (and hence the low- intermediate-resolution spectra) of the full system. The application to a “dimer” of anthracene (156 normal modes) delivers absorption and ECD spectra in the region of the 1La monomer transition in very nice agreement with the experiment [7]. Furthermore, the hierarchical representation allows the qualitative assignment of the main vibronic features of the spectra in terms of transitions to states of well-defined “effective” vibrational modes. [1] Padula D, Picconi D, Di Bari L, Lami A, Pescitelli G, Santoro F, J Phys Chem B

submitted. [2] Harada, N.; Nakanishi, K.; Berova, N. In Comprehensive Chiroptical Spectroscopy;

Berova, N.; Woody, R. W.; Polavarapu, P.; Nakanishi, K., Eds.; Wiley: New York, 2012, 1, 115.

[3] Seibt, J.; Engel, V. The Journal of chemical physics 2007, 126, 074110. [4] Pawlikowski, M.; Zgierski, M. Z. The Journal of Chemical Physics 1982, 76, 4789–4797 [5] Guthmuller, J.; Zutterman, F.; Champagne, B. The Journal of chemical physics 2009,

131, 154302. [6] Picconi, D.; Lami, A.; Santoro, F. The Journal of Chemical Physics 2012, 136, 244104. [7] Harada, N.; Takuma, Y.; Uda, H. Journal of the American Chemical Society 1978, 100,

4029.


107

PHOTOPHYSICS & PHOTOCHEMISTRY OF CARBONYL

CAROTENOIDS: A COMBINED CASSCF AND TD-DFT STUDY

Mireia Segado1, Francisco Jose Avila Ferrer2 , Fabrizio Santoro2 ,

Chiara Cappelli3,, Mariangela Di Donato4,5, Andrea Lapini4, Manuela Lima4, Roberto Righini4

1Dipartimento di Chimica e Chimica Industriale, Università di Pisa via Risorgimento, 35 I-56126 Pisa (Italy) & INSTM, UdR Pisa, Dipartimento di Chimica e Chimica Industriale,

Università di Pisa, via Risorgimento, 35 I-56126 Pisa (Italy); 2ICCOM-CNR, Area della Ricerca, via G. Moruzzi 1, I-56124 Pisa, Italy;

3Dipartimento di Chimica e Chimica Industriale, Università di Pisa via Risorgimento, 35 I-56126 Pisa (Italy) & Scuola Normale Superiore Piazza dei Cavalieri, 7 I-56126 Pisa (Italy),

4LENS (European laboratory for non linear spectroscopy) via N. Carrara 1, 50019 Sesto Fiorentino (FI) Italy;

5Dipartimento di Chimica ‘Ugo Schiff’, Universita’ di Firenze, via della Lastruccia 13, 50019 Sesto Fiorentino (FI), Italy.

The aim of this work is to clarify the nature of the evolution of the first bright electronic, the nature of low lying electronic states and elucidate the role ICT states in apocarotenals. The study is focused on two carotenoids; trans-8’-apo-β-carotenal and trans-12’-apo-β-carotenal. The ordering of the low-lying excited electronic states is very important to define the photochemical properties of these carotenoids. As polyenes, if C2h symmetry is assumed in polyene backbone, 1 Ag − symmetry is predicted for the ground state (S0) of the carotenoid and the presence of several low lying singlet excited states including 21 Ag −,11 Bu -,11 Bu+. In last years the photophysics of carotenoids was be described as a three-state model involving S0 , S1 (1 A− ) and S2 (1 Bu+ ). But It is still a controversy on carotenoids containing electron withdrawing substituents, where mesurements in different solvents show lifetime shortening induced by solvent polarity within the possible presence of an ICT state. Transient infrared spectroscopy (T1D-IR) and transient 2D infrared spectroscopy (T2D-IR) are used to investigate the ultrafast excited state relaxation dynamics. The best features for CASSCF/MS-CASPT2 and TDDFT quantum methods are combined in order to computed and elucidate: a) vibrational resolved absorption electronic spectra, b) nature of low lying excited states c) equilibrium geometries and Hessians of ground and low lying excited state states in order to analyze the geometrical and frequencies changes, focusing on the normal modes active in the IR for the ground and excited states. Based on this global analysis we propose a photochemical mechanism for these systems where only 21 Ag − ,11 Bu + excited state are involved and we suggest 11 Bu + excited state as the ICT state.


108

IRON GALL INKS AS 3D COORDINATION POLYMERS.

A DFT STUDY USING PERIODIC BOUNDARY CONDITIONS

Sara Zaccaron, Marco Bortoluzzi, Renzo Ganzerla

Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia, Dorsoduro 2137, 30123 Venezia, Italy

E-mail: [email protected] Iron gall inks can be prepared mixing an iron salt (usually ferrous sulfate heptahydrate) and gallic acid (3,4,5-trihydroxybenzoic acid). Thanks to their indelibility, these blue-black inks have been the most important writing material in the past, widely used until the 20th century. Although, documents containing iron gall dyes show noticeable degradation phenomena, such as browning and embrittlement, caused by the interaction between metallo-gallate inks and cellulose. Unfortunately, molecular structures and electronic features of iron gall complexes are still not completely ascertained. In the present communication we report the electronic structure of a 3D iron-based coordination polymer having formula [(Fe3L3)

3-]∞ (H4L = gallic acid). It has been studied applying DFT-based computational methods in combination with periodic boundary conditions and plane-waves or numerical basis sets. The model compound has been built on the basis of reported experimental structural parameters. [1] Data regarding the ground-state spin multiplicity, the magnetic interactions among the primitive cells, the charge and spin distributions, the oxidation states, the frontier bands and the band gap have been computed. Moreover, the simulation of the optical properties shows consistency between the calculated absorption spectrum and the commonly reported spectra for iron gall dyes, validating the model here proposed for the electronic structure of [(Fe3L3)

3-]∞, We acknowledge the CINECA Award N. HP10CRPVUO, 2011 for the availability of high performance computing resources and support. [1] a) Wunderlich, C.H. Z Anorg Allg Chem. 1991, 598-599, 371. b) Wunderlich, C.H.

Restauro 1994, 100, 414. c) Zaccaron, S., Bortoluzzi, M., Ganzerla, R. Computational studies on iron-based coordination polymers of interest in cultural heritage, Atti del Primo Congresso Nazionale della Divisione di Chimica Teorica e Computazionale della società Chimica Italiana, pp. 112, Pisa, 22-23 febbraio 2012. d) Zaccaron, S., Bortoluzzi, M., Ganzerla, R, J. Coord. Chem., Submitted. e) Zaccaron, S., Bortoluzzi, M., Ganzerla, R, Sciences at Ca’ Foscari, Submitted.


109

INTEGRATED APPROACHES TO NMR SPIN RELAXATION IN

FLEXIBLE BIOMOLECULES: APPLICATION TO

OLIGOSACCHARIDES

Mirco Zerbetto,a Dmytro Kotsyubynskyy,a Maria Soltesova,b Jozef Kowalewski,b Goran Widmalm,b Antonino Polimenoa

a Dipartimento di Scienze Chimiche, Università degli Sutdi di Padova, Padova 35131, Italy b Department of Physical, Inorganic and Structural Chemistry, Stockholm University,

10691 Stockholm, Sweden We address the interpretation of molecular dynamics from nuclear magnetic resonance measurements (NMR) of flexible molecules via stochastic modeling. We focus our attention to the family of flexible molecules which internal relevant dynamics, with respect to NMR observables, is expressed in terms of torsion angles. Thus, we deal with molecules that from the point of view of the NMR spectroscopy can be associated to chains of rigid fragments connected by joints around which torsion is possible. The complete dynamics comprises the, coupled, global tumbling and internal flexibility. Here we apply two different approaches to the interpretation of slow dynamics of close- and open-chain oligosaccharide molecules, which have a primary interest in the fields of biology (e.g. cellular recognition) and of theoretical/computational chemistry, as tunable case-study systems. In particular, we apply a mesoscopic two-body approach [1, 2] to close-chain cyclodextrins and a many-body diffusive model approach [3] to selected open-chain oligosaccharides, in which torsion angles are explicitly taken into account. We also show that by merging the stochastic treatment to quantum mechanical, molecular dynamics, and hydrodynamics methods, many of the molecular properties entering the stochastic model can be evaluated a priori leaving a very reduced set of (or even none) free parameters to be determined by fitting. [1] Polimeno, A.; Freed, J. H. J. Phys. Chem. 1995, 99, 10995-11006. [2] Zerbetto, M.; Kotsyubynskyy, D.; Kowalewski, J.; Widmalm, G.; Polimeno, A. J. Phys.

Chem. B 2012, 116, 13159-13171. [3] Kotsyubynskyy, D.; Zerbetto, M.; Soltesova, M.; Engström, O.; Pendrill, R.; Kowalewski,

J.; Widmalm, G.; Polimeno, A. J. Phys. Chem. B 2012, 116, 14541-14555.


110

SPECTROSCOPIC PROPERTIES OF THIOPHENE BASED

EUROPIUM ββββ-DIKETONATE COMPLEXES:

A THEORETICAL STUDY

Ugo Cosentinoa, Claudio Grecoa, Giorgio Morob, Luca Bertinib,

Malgorzata Biczysko,c Vincenzo Baronec

aDipartimento di Scienze dell’Ambiente e del Territorio e di Scienze della Terra, Università di Milano-Bicocca; Piazza della Scienza 1, 20126 Milano, Italy

bDipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca; Piazza della Scienza 2, 20126 Milano, Italy

cScuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy e-mail: [email protected]

Due to their photophysical properties, Lanthanide complexes with π-conjugated ligands can act as light antennae, and thus find applications in several technological fields. [1]One of the most studied class of ligands is constituted by β-diketonateligands (β-DK) in view of their noticeable emission properties due to the effectiveness of the energy transfer (ET) from this ligand to the Ln(III) ion. In particular, europium β-DK complexes have attracted more interest in optoelectronic applications because of their strong and narrow red emission.

Here we present the results of our theoretical investigation on the spectroscopic properties of the Eu(TTA)3Phen (1), Eu(Br-TTA)3Phen (2), Eu(DTDK)3Phen (3), and Eu(MeT-TTA)3Phen (4) complexes (Scheme 1 for ligand structures), the photophysical characterization of which has been recently reported in literature. [2] The adiabatic transition energies from the lowest triplet states of compounds (1)-(4) have been determined in CH2Cl2solution by the ∆SCF method at the DFT theory level, using the PBE1PBE and the CAM-B3LYP hybrid functionals. Calculations, performed with the Gaussian 09 program, were done by using for the Europium ion a large-core quasi-relativistic effective core potential (ECP)

NNPhen

(1) TTA

(3) DTDK (4) MeT-TTA

(2) Br-TTA

SCF3

O OS

CF3

O OBr

SO O

S

S

SCF3

O O

CH3


111

and the related [5s4p3d]-GTO valence basis set and for the ligand atoms, the 6-31G* basis. As a result, the adiabatic transitions of compounds (1)-(4) calculated in solution including ZPE corrections by the two functional well reproduce the experimental 0-0 transitions determined from phosphorescence spectra of the corresponding Gd3+ complexes. These results confirm the reliability of the adopted computational procedure in calculating the lowest triplet state energy of these complexes, a critical parameter in determining the photoluminescence quantum yields of these systems. [1] Bünzli, J-C. G.; Piguet, C. Chem. Soc. Rev. 2005, 34, 1048. [2] Freund, C.; Porzio, W.; Giovanella, U.; Vignali, F.; Pasini, M.; Destri, S.; Mech, A.; Di

Pietro S.; Di Bari, L.; Mineo, P., Inorg. Chem. 2011, 50, 5417.


112

COMPUTATIONAL SPECTROSCOPY FOR SYSTEMS IN THE

CONDENSED PHASE: NICOTINE AS A TEST CASE

Franco Egidi,a Julien Bloino,a,b Chiara Cappellia,c , Vincenzo Baronea

a Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy b CNR, Istituto di Chimica dei Composti Organometallici, UOS di Pisa,

Via G. Moruzzi 1, 56124 Pisa, Italy

c Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, 56126 Pisa, Italy

Reliable computations of spectroscopic parameters for flexible molecules in condensed phases require a proper account of stereo-electronic, dynamic, and environmental effects [1,2] if they are to be compared directly to experiment. In the framework of last-generation density functionals, these effects can be introduced by second order vibrational perturbation theory [4,5] coupled to polarizable continuum models [6,7]. In this communication we present a thorough computational spectroscopic analysis of nicotine as a test case which includes the calculation of the NMR shieldings and spin-spin couplings, optical rotation, infra-red and vibrational circular dichroism spectra, and raman optical activity spectra to show the reliability and applicability of our methodology. [1] Barone, V.; Improta, R.; Rega, N. Acc. Chem. Res. 2008, 41, 605-616. [2] Barone, V.; Baiardi, A.; Biczysko, M.; Bloino, J.; Cappelli, C.; Lipparini, F.; Phys. Chem.

Chem. Phys. 2012, 14, 12404-12422. [3] Barone, V. J. Phys. Chem. A 2004, 108, 4146-4150. [4] Barone, V. J. Chem. Phys. 2005, 122, 014108. [5] Tomasi, J.; Mennucci, B.; Cammi, R. Chem. Rev. 2005, 105, 2999-3093. [6] Mennucci, B. WIREs Comput. Mol. Sci. 2012, 2, 386-404.


113

QUANTUM CHEMISTRY WITHOUT WAVEFUNCTIONS:

NEW PROSPECTIVES

Stefano Conte

Department of Chemistry, University of Pisa, Italy

E-mail: [email protected]

Electron Correlation has a crucial role in modern Quantum Chemistry: the direct calculation of the two-electron reduced density matrix (2-RDM) requires the trasformation of the N-electron wave function to density matrix. A variational 2-RDM procedure, using first-order semidefinite programming, has been shown to capture multireference correlation effects important at non-equilibrium geometries. The nonvariational calculation of the 2-RDM requires the contracted Schroedinger equation. In fact the many-electron problem might be reducible to only two electrons: the energy of any atom or molecule can be expressed as a linear functional of the 2-RDM with only density matrix, without wave functions, because electrons are indisinguishable with only pairwise interactions. The 2-RDM had to be costrained to represent a many-electron density matrix: these constraints have called N-reperesentability conditions and become known as the N-representability problem. These 2-RDM methods have been applied in a variety of problems including (i) the conical intersections in methylene and bicyclobutane, (ii) the biolumniscence of fireflies, (iii) quantum phase transitions, (iv) the study of the ground-state motion of nuclei within the Born-Oppenheimer approximation. These 2-RDM methods have the ability to treat moderate-to-strong Electron Correlation in Chemistry and Physics that is especially difficult for traditional wave functions methods. [1] R. McWeeny, “Quantum Chemistry: the first seventy years”, Spiers Memorial Lectures,

Faraday Discussions, 135, 2007. [2] J. Schiff, B. Poirier, “Quantum Mechanics without Wave Functions”, J. Chem. Phys.

2012, 136. [3] D. A. Mazziotti, “Quantum Chemistry without Wave Functions”, Accounts of Chemical

Research of the ACS 2006, 39, 3. [4] J. A. Coleman, V. I. Yukonov, “Reduced Density Matrices”, Springer-Verlag, New York,

2000. [5] D. A. Mazziotti, “Reduced-Density-Matrix Mechanics”, Wiley, New York, 134, 2007. [6] D. A. Mazziotti, “Two-Electron Reduced Density Matrix as the Basic Variable in Many-

Electron Quantum Chemistry and Physics”, Chemical Reviews of the ACS 2011.


114

PREDICTING THE SPIN-STATE ENERGETICS AND NMR

OF IRON COMPLEXES BY DFT

Andrea Borgogno, Federico Rastrelli, Alessandro Bagno*

Department of Chemistry, University of Padova.

*[email protected] Many transition-metal complexes can exist in different electron configurations, leading in turn to different spin states. The most studied example is probably that of iron(II) (d6). According to the kind of coordinated ligands, Fe(II) complexes may exist as a singlet (S=0), triplet (S = 1) or quintet (S = 2) state. Likewise, Fe(III) complexes (d5) can exist in the S = 1/2, S = 3/2 and S = 5/2 states. Similar situations occur also in the case of other transition metals, of course. The spin state of a given complex is not always straightforward to predict. Also, when the separation between the energy of such states is small, even subtle changes in the ligands cause a switch in the relative stability. This phenomenon acquires a major significance whenever the spin transition can be triggered by external factors such as temperature or light, giving rise to spin-crossover (SCO), which is being investigated for information storage. [1] It is therefore desirable to be able to predict and probe the spin state of such complexes, since this capability would allow to design complexes and monitor their properties. Here, we have applied DFT methods to the prediction of the relative energies of the spin states of a variety of Fe(II,III,IV) complexes (Figure 1). These results are then employed for the prediction of paramagnetic NMR spectra, which allows one to simplify the interpretation of experimental results compromised by line broadening and paramagnetic shifts. [2] In order to achieve this goal, a computational method that is sufficiently accurate and inexpensive for NMR calculations [3] is required. Thus, the performance of several (GGA, meta-GGA and hybrid) density functionals has been tested, and B3LYP* was found to provide the best results. These results were used to compute the NMR spectra of several Fe complexes in various spin states.

Figure 1: Examples of Fe(II) A, Fe(III) B and Fe(IV) investigated complexes.


115

[1] Halcrow M. A., Chem. Soc. Rev. 2011, 40, 4119-4142. [2] Bertini I., Luchinat C., Parigi G., “Solution NMR of Paramagnetic Molecules

Applications to Metallobiomolecules and Models”, Elsevier, Amsterdam, 2001. [3] Bagno A., Rastrelli F., Chem. Eur. J. 2009, 15, 7990-8004.


116


117

INDICE DEGLI AUTORI

A Alagia, M. .....................................................................95 Albanese, E. ............................................................57; 72 Albertí, M......................................................................76 Albini, A..................................................................98; 99 Alcaro, S........................................................................26 Alessio, M. ....................................................................71 Andreussi, O..................................................................19 Aquilanti, V...................................................................24 Argeri, M.................................................................35; 58 Armata, N................................................................60; 77 Artese, A. ......................................................................26 Avila Ferrer, F. J. ............................................45; 61; 107

B Bagno, A. ......................................................99; 103; 114 Baima, J.............................................................62; 73; 86 Balducci, G..................................................................100 Barolo, C. ......................................................................58 Barone, V. ...........................................3; 22; 84; 110; 112 Baseggio, O...................................................................63 Bernardi, A......................................................................4 Bertini, L. ........................................................64; 65; 110 Biancardi, A. .................................................................20 Biczysko, M. ...............................................................110 Bindu Kolli, H...............................................................31 Biver, T. ........................................................................20 Bloino, J. .....................................................................112 Bodo, E. ..................................................................21; 95 Bonačić-Koutecký, V. ...................................................65 Bonfanti, M. ..................................................................10 Borgogno, A................................................................114 Bortoluzzi, M. .............................................................108 Brancato, G. ..................................................................84 Bruschi, M.........................................................36; 64; 65 Buonfiglio, R.................................................................90 Butera, V. ......................................................................14

C Calabrese, V. .................................................................43 Calderini, D...................................................................24 Caminiti, R. ...................................................................21 Cancès, E.......................................................................39 Cantatore, V. .................................................................66 Canti, L. ..................................................................35; 68 Cappelli, C. .....................................................5; 107; 112 Carlotto, S. ....................................................................70 Carnimeo, I....................................................................22 Carter, E. A. ............................................................41; 44 Carteret, C. ....................................................................28 Casarin, M...............................................................78; 87 Casassa, S......................................................................86 Casatti, M. .....................................................................26 Casazza, S. ....................................................................74 Casolo, S. ......................................................................10 Cassani, S. .....................................................................82

Cavalli, A. ..................................................................... 90 Cavazzini, M................................................................. 43 Cerezo, J. ...................................................................... 61 Charpentier, T. ........................................................ 11; 32 Chirico, N. .................................................................... 82 Cinacchi, G. .................................................................. 31 Civalleri, B.................................................. 57; 71; 72; 88 Coccia, E....................................................................... 23 Coletti, C................................................................. 24; 49 Comotti, A. ................................................................... 79 Conte, S....................................................................... 113 Coriani, S. ....................................................................... 6 Cortese, R. .............................................................. 25; 77 Cosentino, U. .............................................................. 110 Cossi, M...................................................... 35; 58; 68; 79 Costa, G. ....................................................................... 26 Costantini, A. ................................................................ 37 Crestoni, M. E............................................................... 49 Curutchet, C.................................................................. 52

D De Gioia, L. ...................................................... 36; 64; 65 De La Pierre, M. ..................................................... 28; 73 Decleva, P. ........................................................ 51; 94; 95 Demontis, P........................................................... 50; 105 Di Donato, M. ............................................................. 107 Di Marino, M. ............................................................... 78 Di Valentin, Cristiana ................................................... 75 Distinto, S. .................................................................... 26 Dondi, D. ...................................................................... 99 Dovesi, R. ....................................... 28; 29; 62; 73; 85; 89 Duca, D. .................................................................. 25; 77

E Egidi, F. ...................................................................... 112 Erba, A.............................................................. 29; 57; 62

F Faginas Lago, N............................................................ 76 Fagnoni, M.............................................................. 98; 99 Falchi, F. ....................................................................... 90 Falcinelli, S. .................................................................. 95 Fantucci, P. ....................................................... 36; 64; 65 Ferrabone, M........................................................... 29; 85 Ferrante, F......................................................... 25; 60; 77 Ferrari, A. M. .......................................................... 30; 74 Ferrarini, A. ................................................ 31; 81; 83; 92 Ferraro, M. .................................................................... 90 Ferrero, M. .................................................................... 85 Fornarini. S. .................................................................. 49 Forrer, D. ...................................................................... 78 Fortunelli, A.................................................................... 7 Fraccarollo, A. .................................................. 35; 68; 79 Frezza, E. ...................................................................... 31 Frezzato, D.................................................................... 80 Fronzoni, G. .......................................................... 63; 100


118

G Gabrieli, A...................................................................105 Galeazzi, R. ...................................................................91 Gambuzzi, E..................................................................32 Ganzerla, R..................................................................108 Gasparotto, P.................................................................81 Giacometti, A. ...............................................................31 Giammarino, G..............................................................53 Giordano, L. .................................................................34 Giordano, L. ..................................................................30 Glisenti, A. ....................................................................70 Gramatica, P..................................................................82 Granucci, G. ..................................................................66 Grassi, F. .................................................................35; 58 Greco, Claudio ..........................................36; 64; 65; 110 Greco, Cristina ..............................................................83 Grisanti, L. ...................................................................43 Grubisic, S.....................................................................84 Guidoni, L. ....................................................................23

I Improta, R. ..............................................................45; 61

J Ji, Y. ............................................................................102

K Karamanis, P. ................................................................73 Kirtman, B...............................................................85; 89 Kotsyubynskyy, D.......................................................109 Kovarich, S....................................................................82 Kowalewski, J. ............................................................109

L Lacivita, V.....................................................................85 Laganà, A. .....................................................................37 Lami, A. ........................................................................45 Lapini, A. ....................................................................107 Lazzara, G. ....................................................................60 Lima, M.......................................................................107 Lipparini, F....................................................................39 Lo Celso, F....................................................................77

M Maccioni, E. ..................................................................26 Maday, Y.......................................................................39 Mahmoud, A. ................................................................86 Mangione, G..................................................................87 Marchese, L.................................................35; 58; 68; 79 Marino, T. .....................................................................40 Martinazzo, R................................................................10 Marzari, N. ....................................................................19 Maschio, L. .....................................................88; 89; 104 Masetti, M. ..............................................................12; 90 Masia, M. ......................................................................50 Massaccesi, L. ...............................................................91 Mennucci, B. .................................................9; 20; 39; 52 Menziani, M. C. ..........................................11; 32; 47; 96 Milioto, S. .....................................................................60 Mitri ć, R........................................................................65 Mobbili, G.....................................................................91 Moraca, F. .....................................................................26

Moro, Giorgio ............................................................. 110 Muñoz-Garcia, A. B...................................................... 44 Muñoz-García, A. B...................................................... 41 Musetti, C. .................................................................... 26

N Nardi, M........................................................................ 87 Natile, M. M.................................................................. 70

O Orlando, R............................................. 42; 62; 72; 85; 89 Ortuso, F. ...................................................................... 26

P Pacchioni, G............................................................ 34; 75 Paciotti, R. .................................................................... 49 Painelli, A. .................................................................... 43 Papa, E. ......................................................................... 82 Parisio, G. ............................................................... 81; 92 Parrotta, L. .................................................................... 26 Pavone, M. .............................................................. 41; 44 Pedone, A.................................................... 11; 32; 47; 96 Persico, M. .................................................................... 66 Picconi, D. .................................................................... 45 Pisani, C........................................................................ 29 Pisani, M. ...................................................................... 91 Polimeno, A. ............................................................... 109 Pomelli, C. S. ................................................................ 93 Ponzi, A. ................................................................. 94; 95 Prada, S......................................................................... 34 Presti, D. ................................................................. 47; 96 Prestianni, A............................................................ 25; 77 Protti, S. ........................................................................ 98

Q Quici, S. ........................................................................ 43

R Rastrelli, F................................................................... 114 Ravelli, D................................................................ 98; 99 Re, N............................................................................. 49 Recanatini, M.......................................................... 12; 90 Rérat, M. ........................................................... 62; 85; 89 Richter, R...................................................................... 95 Righini, R.................................................................... 107 Romeo, M. ............................................................ 63; 100 Rosa, M......................................................................... 75 Russo, N.................................................................. 14; 40

S Saielli, G. ............................................................ 102; 103 Salustro, S. .................................................................. 104 Sambi, M....................................................................... 78 Sant, M........................................................................ 105 Santoro, F................................................ 45; 61; 106; 107 Savin, A. ....................................................................... 88 Scalmani, G................................................................... 22 Sedona, F. ..................................................................... 78 Segado, M. .................................................................. 107 Sharkas, K..................................................................... 88 Shi, R. ......................................................................... 102


119

Sicilia, E........................................................................14 Sissa, C..........................................................................43 Sissi, C. .........................................................................26 Soltesova, M................................................................109 Stamm, B.......................................................................39 Stendardo, E. .................................................................61 Stener, M...............................................................63; 100 Stranger, S.....................................................................95 Suffritti, G. B.........................................................50; 105

T Tantardini, G. F. ............................................................10 Tarantelli, F. ..................................................................13 Terenziani, F. ................................................................43 Toffoli, D. .....................................................................51 Toulouse, J. ...................................................................88

V Valenzano, L. ................................................................72

Varsano, D. ................................................................... 23 Verucchi, R. .................................................................. 87 Viani, L......................................................................... 52 Villani, V. ..................................................................... 53 Vittadini, A. ...................................................... 15; 70; 78 Voth, A. ...................................................................... 102

W Wang, F......................................................................... 75 Wang, Y...................................................................... 102 Widmalm, G................................................................ 109

Z Zaccaron, S. ................................................................ 108 Zagotto, G. .................................................................... 26 Zampella, G. ........................................................... 64; 65 Zerbetto, M. .......................................................... 80; 109


120


121

ELENCO DEI PARTECIPANTI

Albanese Elisa [email protected] Dipartimento di Chimica

Università degli Studi di Torino

Andreussi Oliviero [email protected]

Dipartimento di Chimica e Chimica Industriale

Universita’ di Pisa

Argeri Mario [email protected]

Dipartimento di Scienze e Tecnologie Avanzate (DISIT)

Università del Piemonte Orientale A.Avogadro

Armata Nerina [email protected] Dipartimento di Fisica e Chimica

Università degli Studi di Palermo

Aschi Massimiliano [email protected] Dipartimento Scienze Fisiche e Chimiche

Università di l’Aquila

Avila Ferrer

Francisco Jose

[email protected] ICCOM

CNR – Consiglio Nazionale delle Ricerche

Bagno Alessandro [email protected] Scienze Chimiche Università di Padova

Baima Jacopo [email protected] Chimica Università di Torino

Barone Vincenzo [email protected] Classe di Scienze Scuola Normale superiore

Baseggio Oscar [email protected] Dipartimento di Scienze Chimiche e Farmaceutiche

Università degli Studi di Trieste

Bassan Arianna [email protected] S-In Soluzioni Informatiche

Industria

Belpassi Leonardo [email protected] ISTM-CNR CNR

Bernardi Anna [email protected] Dipartimento di Chimica

Universitaà degli Studi di Milano

Bertini Luca [email protected] Dipartimento di Biotecnologie e Bioscienze

Università di Milano-Bicocca

Biancardi Alessandro [email protected] Dipartimento di Chimica

Università di Pisa

Bodo Enrico [email protected] Dipartimento di Chimica

La Sapienza


122

Borgogno Andrea [email protected] Dipartimento Scienze Chimiche

Università di Padova

Bruschi Maurizio [email protected]

Dipartimento di Scienze dell’Ambiente e del Territorio e di Scienze della Terra


Cantatore Valentina [email protected]


Università di Pisa

Canti Lorenzo [email protected]

Dipartimento di Scienze ed Innovazione Tecnologica

Università degli Studi del Piemonte Orientale “Amedeo Avogadro”

Cappelli Chiara [email protected] Classe di Scienze Scuola Normale Superiore

Carlotto Silvia [email protected] Dipartimento di Scienze Chimiche


Carnimeo Ivan [email protected] Classe di Scienze Scuola Normale Superiore

Casarin Maurizio [email protected] Dipartimento di Scienze Chimiche


Casassa Silvia Maria [email protected] Dipartimento di Chimica

Università di Torino

Casolo Simone [email protected] Dipartimento di chimica

Università degli Studi di Milano

Civalleri Bartolomeo [email protected] Dipartimento di Chimica


Coccia Emanuele [email protected] Dipartimento di Scienze Fisiche e Chimiche

Università dell'Aquila

Coden Maurizio [email protected] Dipartimento di Scienze Chimiche


Coletti Cecilia [email protected] Dipartimento di Farmacia

Università G. d'Annunzio Chieti-Pescara

Conte Stefano [email protected] Dipartimento di Chimica

Università di Pisa

Coriani Sonia [email protected] Dipartimento di Chimica

Università di Trieste


123

Cortese Remedios [email protected] Dipartimento di Fisica e Chimica


Cosentino Ugo [email protected]

Dip. Scienze Ambiente e Teritorio e Scienze della Terra

Università Milano-Bicocca

Costa Giosuè [email protected] Dipartimento di Scienze della Salute

Università di Catanzaro

De La Pierre

Marco [email protected] Dipartimento di Chimica


Decleva Piero [email protected] Dipartimento di Scienze chimiche e farmaceutiche


Di Valentin

Cristiana [email protected] Dip. di Scienza dei Materiali


Dovesi Roberto [email protected] Dipartimento di Chimica


Duca Dario [email protected] Dipartimento di Fisica e Chimica


Egidi Franco [email protected] Classe di Scienze Scuola Normale Superiore

Elisa Gambuzzi [email protected] Dip di scienze chimiche e geologiche

Università degli studi modena e reggio emilia

Erba Alessandro [email protected] Dipartimento di Chimica


Ferrari Anna Maria [email protected] Dipartimento di Chimica


Ferrarini Alberta [email protected] Dipartimento di Scienze Chimiche


Ferrante Camilla [email protected] Dipartimento di Scienze Chimiche


Forrer Daniel [email protected] ISTM CNR

Fortunati Nicola [email protected] Dipartimento di Scienze Chimiche


Fortunelli Alessandro [email protected] IPCF CNR

Fraccarollo Alberto [email protected] Dipartimento di Scienze e Innovazione

Università degli Studi del Piemonte


124

Tecnologica Orientale "Amedeo Avogadro"

Frezza Elisa [email protected] Dipartimento di Scienze Chimiche

Università degli studi di Padova

Frezzato Diego [email protected] Dipartimento di Scienze Chimiche


Fronzoni giovanna [email protected] Dipartimento di scienze chimiche e farmaceutiche


Galeazzi Roberta [email protected] Dipartimento di Scienze della Vita e dell'Ambiente

Università Politecnica delle Marche

Gasparotto Piero [email protected] Dipartimento di Scienze Chimiche


Gianturco Francesco A. [email protected] Dipartimento di Chimica

Università di Roma "La Sapienza"

Giordano Livia [email protected] Dipartimento di Scienza dei Materiali


Gramatica Paola [email protected] Dipartimento di Scienze Teoriche e Applicate

Università degli studi dell'Insubria

Grassi Fabio [email protected]

Dipartimento di Scienze ed Innovazione Tecnologica

Università del Piemonte Orientale A. Avogadro

Greco Claudio [email protected]

Dipartimento di Scienze dell'Ambiente e del Territorio

Università degli Studi di Milano Bicocca

Greco Cristina [email protected] Dipartimento di Scienze Chimiche


Grubisic Sonja [email protected] Gruppo di Chimica Teorica e Computazionale

Scuola Normale Superiore

Guarnetti Prandi

Ingrid [email protected]


Università di Pisa

Jurinovich Sandro [email protected]


Università di Pisa

Lacivita Valentina [email protected] Dipartimento di Chimica


Laganà Antonio [email protected] Dipartimento di Chimica

Università di Perugia


125

Laganà noelia [email protected] Dipartimento di chimica


Lipparini Filippo [email protected] Institut du calcul et de la simulation

Université Pierre et Marie Curie

Mahmoud Agnes Nora [email protected] Dipartimento di Chimica IFM


Mangione Giulia [email protected] Dipartimento di Scienze Chimiche


Marinelli Luciana [email protected] Chimica Farmaceutica e Tossicologica

Università degli studi di Napoli "Federico II"

Marino Tiziana [email protected]

Dipartimento di Chimica e Tecnologie Chimiche

Università della Calabria

Martinazzo Rocco [email protected] Dipartimento di Chimica


Maschio Lorenzo [email protected] Dipartimento di Chimica


Masetti Matteo [email protected] Dipartimento di Farmacia e Biotecnologia

Università di Bologna

Massaccesi Luca [email protected] Dipartimento di Scienze della Vita e dell'Ambiente

Università Politecnica delle Marche

Mennucci Benedetta [email protected] Dipartimento di Chimica

Università di Pisa

Moro Giorgio [email protected] Dipartimento di Biotecnologie e Bioscienze


Moro Giorgio [email protected] Dipartimento di Scienze Chimiche


Moro Stefano [email protected] Dipartimento di Scienze del Farmaco


Munoz Garcia

Ana Belen [email protected] Dipasrtimento di Scienze Chimiche

Università di Napoli “Federico II”

Orian Laura [email protected] Dipartimento di Scienze Chimiche


Orlando Roberto [email protected] Dipartimento di Chimica


Pacchioni Gianfranco [email protected] Dipartimento di Scienza dei Materiali

Università Milano Bicocca


126

Painelli Anna [email protected] Dipartimento di Chimica

Università di Parma

Parisio Giulia [email protected] Dipartimento di Scienze Chimiche


Pavone Michele [email protected] Dipartimento di Scienze Chimiche

Università di Napoli “Federico II”

Pedone Alfonso [email protected] Dipartimento di Scienze Chimiche e Geologiche

Università di Modena e Reggio Emilia

Picconi David [email protected] Lehrstuhl fur Theoretische Chemie

Technische Universitaet Muenchen

Polimeno Antonino [email protected] Dipartimento di Scienze Chimiche


Pomelli Christian Silvio

[email protected] Dipartimento di Farmacia

Università di Pisa

Ponzi Aurora [email protected] Dipartimento di Scienze chimiche e farmaceutiche


Presti Davide [email protected] Dipartimento di Scienze Chimiche e Geologiche

Università di Modena e Reggio-Emilia

Ravelli Davide [email protected] Dipartimento di Chimica

Università di Pavia

Re Nazzareno [email protected] Dipartimento di Farmacia

Università G. D'Annunzio Chieti-Pescara

Recanatini Maurizio [email protected] Dipartimento di Farmacia e Biotecnologia

Università di Bologna

Romeo Michele [email protected] Dipartimento di Scienze Chimiche e Farmaceutiche

Università degli Studi di Trieste

Saielli Giacomo [email protected]

Istituto per la Tecnologia delle Membrane, Unità di Padova

CNR

Salustro Simone [email protected] Dipartimento di Chimica


Sant Marco [email protected] Dipartimento di Chimica e Farmacia

Universita' degli Studi di Sassari

Santoro Fabrizio [email protected] ICCOM CNR


127

Segado Centellas

Mireia [email protected]


Università di Pisa

Sicilia Emilia [email protected] Dipartimento di Chimica

Università della Calabria

Stener Mauro [email protected] Dipartimento di Scienze Chimiche e Farmaceutche


Suffritti Giuseppe B. [email protected] Dipartimento di Chimica e Farmacia

Università degli studi di Sassari

Tantardini Gian Franco [email protected] Dipartimento di Chimica


Tarantelli Francesco [email protected] Dipartimento di Chimica


Toffoli Daniele [email protected] Department of Chemistry

Middle East Technical University

Torsello Mauro [email protected] Dipartimento di Scienze Chimiche


Viani Lucas [email protected] Dipartimento di chimica e chimica industriale

Università di Pisa

Villani Vincenzo [email protected] Dipartimetno di Scienze

Università degli Studi della Basilicata

Vittadini Andrea [email protected] Istituto di Scienze e Tecnologie Molecolari

CNR

Zaccaron Sara [email protected]

Dipartimento di Scienze Molecolari e Nanosistemi

Università Ca' Foscari Venezia

Zerbetto Mirco [email protected] Dipartimento di Scienze Chimiche


DCTC13 book FINALE · NMR spectroscopy and accurate first principle calculations 17:15-17:30 Lucas...

Documents

Transcript of DCTC13 book FINALE · NMR spectroscopy and accurate first principle calculations 17:15-17:30 Lucas...