ERC AdG Barone DREAMS 2 DECEMBER 2017 FINAL MEETINGsmart.sns.it/erc2017/20171129-1202 ERC-DREAMS Final OPUSCOLO WEB.pdf · 2 DECEMBER 2017 FINAL MEETING Elaborazione a cura del Servizio

Funded by ERC DREAMS GA n. 320951

Advances in computational modelling: from isolated molecules to soft matter

29 NOVEMBER2 DECEMBER

2017FINAL MEETING

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http://smart.sns.it/erc2017/

Scientific Secretary: [email protected]

Sala AzzurraScuola Normale Superiore

Pisa - Italy

ERC AdG | Barone | DREAMS

BOOK OF ABSTRACTS

Rationale

3ERC-AdG DREAMS 2017

The focus of this meeting – in the frame of the ERC-AdG DREAMS project – is on the computational modelling of molecules in gas and condensed phases, also addressing the increasing complexity from small-/medium-sized molecular species to soft matter.

In the spirit of the DREAMS project, which aimed at developing integrated theoretical-computational approaches for the effective description of linear and non-linear spectroscopies of molecular probes, isolated and embedded in complex environments, the meeting will gather together experimentalists and theoreticians in the fields of computational chemistry, molecular spectroscopy and dynamics, in view of sharing approaches and methodologies to model molecular systems that are, from different points of view, complex.

The meeting will also act as a platform to exchange ideas and promote collaborations within a broad community of researchers as well as to involve students and young scientists (who are encouraged to participate).

ORGANIZING COMMITTEEVincenzo Barone | Chair(Scuola Normale Superiore)

Giordano Mancini(Scuola Normale Superiore)

Sergio Rampino(Scuola Normale Superiore)

Nicola Tasinato(Scuola Normale Superiore)

Monica Sanna | Scientific Secretary (Scuola Normale Superiore)

Funded by ERC DREAMS GA n. 320951

Scientific Program Scientific Program

4 5ERC-AdG DREAMS 2017ERC-AdG DREAMS 2017

29 NOVEMBER 2017 16.00 Registration

17.30 Visit: PALAZZO BLU MUSEUM

19:00 Welcome Buffet

30 NOVEMBER 2017 Session chair, VINCENZO BARONE 09:00 Registration

09:30 Opening by VINCENZO BARONE, Chair

09:45 MICHAEL FRISCH - Gaussian, Inc.New variational and quantum Monte Carlo methods for the prediction of vibrational spectra

10:15 ALBERTO BAIARDI - Scuola Normale SuperioreVibrational Density Matrix Renormalization Group (vDMRG)

10:30 CRISTINA PUZZARINI - Università di BolognaModeling of isolated molecules: a joint computational-spectroscopic approach

11.00 Coffee Break

Session chair, MAURO STENER11:30 WALTHER CAMINATI - Università di Bologna

Chemical information from the rotational studies of homo and hetero binary mixtures of carboxylic acids

12:00 LORENZO SPADA - Scuola Normale SuperioreNoncovalent Interactions and Internal Dynamics in Pyridine–Ammonia: A Combined Quantum-Chemical and Microwave Spectroscopy Study

12:15 LUCA EVANGELISTI - Università di BolognaApplications of Molecular Rotational Spectroscopy for Chiral Analysis

12:30 JAMES CHEESEMAN - Gaussian, Inc.Theoretical prediction of resonance Raman and resonance Raman optical activity spectra

13:00 Lunch

15:00 GIORDANO MANCINI - Scuola Normale Superiore Standing on the shoulders of atoms: scientific visualization in DREAMS

15:15 ANDREA SALVADORI - Scuola Normale SuperioreExploiting Immersive Virtual Reality for the analysis of chemical bonding

15:30 Visit: PALAZZO CAROVANA, LIBRARY & CAVE-3D

18:30 Poster session & Cocktail party

1 DECEMBER 2017 Session chair, NICOLA TASINATO09:00 CHIARA CAPPELLI - Scuola Normale Superiore

Fully polarizable embedding model for molecular spectroscopy of aqueous solutions

09:30 GIANNI CARDINI - Università degli Studi di FirenzeWavelet Transform for Spectroscopic Analysis

09:45 DANIELE LICARI - Scuola Normale SuperioreUser-friendly access to the Virtual Multifrequency Spectrometer

10:00 MARCO FUSÈ - Scuola Normale SuperioreChiral properties of transition metal complexes studied through computational vibrational spectroscopy

10:15 MALGORZATA BICZYSKO - Shanghai UniversityVibrational “fingerprints” of biomolecules building-blocks

10.45 Coffee Break

Session chair, SERGIO RAMPINO 11:15 WALTER ROCCHIA - Istituto Italiano di Tecnologia

Molecular dynamics-based enabling tools for drug design

11:45 GIANLUCA DEL FRATE - Scuola Normale SuperioreParameterization of non-bonded models of metal ions using statistical learning techniques

12:00 SARA DEL GALDO - Scuola Normale SuperioreCombining Molecular Dynamics and the Perturbed Matrix Method to study Tyrosine UV-Vis spectroscopic properties

Scientific Program Scientific Program


12:15 ALESSANDRO FORTUNELLI - ICCOM-CNR U.O.S. PisaAnalysis of theoretical absorption and circular dichroism spectra of complex systems: the case of monolayer-protected clusters

12:30 ANDREAS DREUW - University of HeidelbergOrganic photochemistry in condensed phases using ADC methods

13:00 Lunch

Session chair, FRANCESCO CIARDELLI15:00 CARLO ADAMO – Chimie ParisTech

Modeling environmental effects on excited electronic states beyond continuum models

15:30 MARIAGRAZIA FORTINO - Università di Modena e Reggio EmiliaVibrationally Resolved Electronic Spectra of Styryl Substituted Bodipys: Benchmark of New Computational Protocols for the Simulation

15:45 FRANCO EGIDI - Scuola Normale SuperioreToward the Accurate Simulation of Vibrationally-Resolved Spectra for Spin-Forbidden Transitions

16:00 UMBERTO RAUCCI - Università degli Studi di Napoli Federico IIExploring ultrafast photodynamics in solution: a new theoretical challenge

16:15 NADIA REGA - Università degli Studi di Napoli Federico IINew models for time resolved processes occurring in excited electronic states

16.45 Coffee Break

Session chair, ANTONIO RIZZO17:15 GIULIO CERULLO – Politecnico di Milano

Two-dimensional electronic spectroscopy from the visible to the ultraviolet

17:45 KENNETH RUUD – University of TromsøModeling nonlinear and multidimensional spectroscopies in complex environments

18:15 LIUDMIL ANTONOV - Bulgarian Academy of SciencesTautomerism and proton transfer: when and if theory meets experiment

18:30 DIMITRIOS SKOUTERIS - Scuola Normale Superiore Formation mechanisms of prebiotic molecules in the interstellar medium

20:30 Social Dinner

2 DECEMBER 2017 Session chair, JULIEN BLOINO 09:00 MARIA PILAR DE LARA-CASTELLS – Consejo Superior de Investigaciones Científicas

Ab-initio computational modeling of molecular motion under confinement

09:30 LUCA MUCCIOLI - Università di BolognaModeling the electromechanical response of rubrene single crystals

09:45 JACOPO FREGONI - Università degli studi di Modena e Reggio EmiliaNon-adiabatic dynamics on hybrid light-matter states

10:00 ANDREA PUCCI - Università di PisaPolymer films with Aggregation Induced Emission: a new tool for optical sensing and energy harvesting

10:15 DEBORA BERTI – Università degli Studi di FirenzeNanoparticles meet biomembranes: insights from experiments and simulations on model lipid bilayers

10.45 Coffee Break

Session chair, VINCENZO BARONE11:15 NINO RUSSO - Università della Calabria

The contribution of computational chemistry to chemo- and photodynamic therapies

11:45 TIZIANA MARINO - Università della CalabriaFrom QM cluster to QM/MM ONIOM simulations: the case of LigW-decarboxylase

12:00 RICCARDO CHELLI - Università degli Studi di FirenzeBinding free energies of host-guest systems by nonequilibrium alchemical simulations with constrained dynamics

12:15 MARIA J. RAMOS – Universidade do Porto Can we accurately predict mechanisms of enzymatic reactions?

12:45 Closing by VINCENZO BARONE, Chair

13:00 Lunch

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Invited Speakers Invited Speakers

ERC-AdG DREAMS 2017ERC-AdG DREAMS 2017

Modeling environmental effects on

excited electronic states beyond continuum models Carlo Adamo

Institut de Recherche de Chimie Paris, PSL Research University, CNRS, Chimie ParisTech, 11 rue Pierre et Marie Curie, F-75005 Paris, France

[email protected]

Albeit polarizable continuum models (PCMs) are powerful and versatile approaches to model solvent

effects on physico-chemical properties, their limitation clearly appears when specific interactions

(electrostatic, H-bonds, VdW interactions) dominate the interactions with the surrounding

environment. In this case, the closest chemical neighbors should be explicitly treated and PCMs could

be used for mimicking medium/long range effects. Of course treating on the same foot (i.e. with the

same Hamiltonian) the solute and the surrounding molecules could quickly lead to large and

cumbersome systems. This is even more true when excited electronic states are involved, since they

require more computational demanding approaches.

Among the different approaches developed to cope with these difficult situations, the ones based on

the ONIOM model are particular effective, particularly when coupled with electronic embedding.

Starting from this model, some applications will be illustrated, involving chromophores in different

environments. In particular it will be stressed that only a wise combination of different ingredients,

including a TD-DFT approach, efficient exchange-correlation functionals, dispersion correction and

PCM bulk effects, gives a good agreement with the experimental data.

Nanoparticles meet Biomembranes: insights from experiments and simulations on model lipid bilayers

Debora Berti1, Costanza Montis1, Paolo Bergese2, Giuseppe Milano3, Pierre Joseph4

1Department of Chemistry “Ugo Schiff”, University of Florence, and CSGI-Florence, Sesto F.no, Florence, Italy

2Department of Molecular and Translation Medicine, and INSTM, University of Brescia, Brescia, Italy

3Dipartimento di Chimica e Biologia Università di Salerno I-84084 Fisciano (Salerno), Italy 4 LAAS-CNRS, Université de Toulouse, CNRS, Toulouse, France

[email protected] The tendency of inorganic or polymeric nanoparticles (NPs) to structurally modify and/or permeate biomembranes requires full elucidation to optimize their biomedical applications and/or minimize health risks in consumer products. We addressed these interactions in a prototypical case study, using different model membrane systems, (giant unilamellar vesicles (GUVs), supported lipid bilayers (SLB) and liposomes) challenged with Au NPs, of different size, shape and surface coating. Each of these structural platforms, even starting from the same lipid composition, has distinct physico-chemical properties and lends itself to investigation with complementary experimental techniques, from bulk to surface to single-object level. Therefore, the combination of experimental observations can provide a detailed picture of the relative contributions to the overall interaction scenario. After an electrostatic and/or surface-energy driven adsorption, the NPs stiffen the region of contact and “freeze” the lipids in raft-like nanoscale domains. Molecular simulations, performed with the Martini model confirmed the experimental observations. Microfluidic-assisted experiments on single GUVs provide further evidence of this membrane stiffening effect. Additionally, a membrane-driven aggregation of nanoparticles was observed, whose extent heavily depends on membrane rigidity and NP surface coatings, which can have important and unforeseen applications for bioanalytical purposes . Given the aggregation-dependent plasmonic properties of the particles, this effect can be exploited in the detection of protein contaminants, as we demonstrated in a case study, involving extracellular vesicle isolation. In vitro experiments performed on and rat macrophages challenged with the same NPs, indicate a close analogy with the observations in synthetic models, providing validation of our experimental approach and indicating a possible roadmap to fully address biomembrane activity of nanoparticles. Acknowledgements Financial support from CSGI and Ente Cassa di Risparmio di Firenze is gratefully acknowledged

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Vibrational “fingerprints” of biomolecules building-blocks Malgorzata Biczysko

Shanghai University, Shanghai, 200444, China [email protected]

Advanced spectroscopic experiments are widely applied for understanding the biomolecules structure-function relationships, allowing a direct detection of different 3D-conformational schemes via microwave (MW) measurements or indirect analysis through 'fingerprint' vibrational features in infrared (IR), Raman, Resonance Raman, UV-vis or fluorescence spectra, including also their chiral counterparts. However, the conformational flexibility and great variety of possible interactions results that these experimental spectroscopic studies are extremely difficult to interpret. In this talk I will present the status and perspectives of the ongoing project aiming to bridge the gap between sophisticated experimental techniques and often over-simplified analysis, focusing specifically on protein and DNA building blocks. In this context, inclusion of anharmonic effects on rotational constants, thermodynamic properties, and on both line positions and intensities of vibrational (IR, Raman, VCD, ROA..) spectra is paving a way toward significantly improved level of accuracy and understanding of state-of-the-art contemporary spectroscopic results. In this framework, computational protocol is developed through a multistep strategy, starting from isolated molecules, oligomers and weakly-bonded complexes/clusters. Extension to larger and more complex systems relies on reduced dimensionality approaches and effective schemes to select transitions of interest. Such procedures will be discussed focusing on the challenges represented by an accurate description of 3D-conformational structure of flexible systems and vibrational modes involved in the inter- or intra-molecular hydrogen bonds.

Figure 1. Step-by-step derivation and validation of computational spectroscopy models, from small bio-

molecules to larger and more flexible oligomers and complexes.

References [1] J. Bloino, A. Baiardi, M. Biczysko Int. J. Quant. Chem. 116 (2016) 1543.

[2] T. Fornaro, M. Biczysko, J. Bloino, V. Barone, Phys.Chem.Chem.Phys. 18, (2016) 8479.

[3] M. Biczysko, J. Bloino, C. Puzzarini, Wires Comp. Mol. Sci. (2017) doi: 10.1002/wcms.1349.

Chemical information from the rotational studies of homo and hetero binary mixtures of carboxylic acids

Walther CaminatiDipartimento di Chimica, Universita’ di Bologna, Via Semi 2, Bologna, Italy

[email protected]

The rotational spectra of many complexes involving carboxylic acids supplied plenty of information on the nature of the involved hydrogen bonds, on the internal dynamics, on the conformational equilibria, and occasionally on the competition between reactivity and pre-reactivity of the. They can be classified as:

1) Dimers of carboxylic acids. Pairs of carboxyl groups bind cooperatively together, since both units act as proton donor and acceptor, forming a large eight-membered ring containing two hydrogen bonds. Such a kind of hydrogen bonding is the strongest one found within neutral species, with the monomers held together by more than 60 kJ/mol. To these strong hydrogen bonds a clearly sizable Ubbelohde effect is associated. Proton tunneling [1] (see Fig. 1), or other kinds of internal dynamics, or conformational equilibria [2], have been observed and described in several cases. Recently, the rotational spectra of three deuterated isotopologues of the dimer of formic acid have been measured, thank to the small dipole moment induced by asymmetric H-->D substitution(s).

Figure 1 Proton transfer between equivalent forms in dimer of carboxylic acids supply a tunneling splitting useful for the barrier determination.

2) Adducts of carboxylic acids with water. The carboxyl group and water act simultaneously as proton donor and proton acceptor, leading to the formation of a six membered ring with two hydrogen bonds. Splittings of the rotational transitions have been observed, not yet satisfactorily attributed to a specific internal motion.

3) Adducts of carboxyic acids with other organic molecules. Mixtures of formic acid with several alcohols, ethers, esters and ketones have been supersonically expanded as pulsed jets. The obtained cool plumes have been analyzed by Fourier transform microwave spectroscopy. It has been possible to assign the rotational spectra of the 1:1 adducts of formic acid with ethers, ketones, esters, but not with every kind of alcohols. In the latter case, primary and secondary alcohols react with the acid giving the ester [3].

References: [1] G. Feng, L. B. Favero, A. Maris, A. Vigorito, W. Caminati, R. Meyer, J. Am. Chem. Soc. 134, 19281

(2012).[2] G. Feng, Q. Gou, L. Evangelisti, W. Caminati, Angew. Chem. Int. Ed. 53, 530 (2014).[3] L. Evangelisti, L. Spada, W. Li, F. Vazart, V. Barone, W. Caminati, Angew. Chem. Int. Ed. 56, 3872

(2017).

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A Fully Polarizable Embedding Model for Molecular Spectroscopy of Aqueous Solutions

Chiara Cappelli11Scuola Normale Superiore, Piazza dei Cavalieri, 7 I-56126 Pisa, Italy

The computational modeling of molecular spectra of aqueous solutions is particulary challenging. In fact, it requires at the same time an accurate modeling of the response of the solute to the external radiation field and a reliable account of the effects of the surrounding environment, which can hugely modify the solute’s spectral features as a result of specific/directional interactions [1]. A recently developed Quantum-Mechanical (QM)/polarizable molecular mechanics (MM)/polarizable continuum model (PCM) [2] embedding approach has shown extraordinary capabilities, yielding calculated spectra in excellent agreement with experiments. An overview of the the theoretical fundamentals of this methods, which combines a fluctuating charge (FQ) approach to the MM polarization with the PCM is given, and specific issues related to the calculation of spectral responses [3] are discussed in the context of selected applications [4]. References [1] F. Egidi, C. Cappelli "Elsevier Reference Module in Chemistry, Molecular Sciences and

Chemical Engineering", DOI:10.1016/B978-0-12-409547-2.10881-9 (2015).

[2] C. Cappelli, Int, J. Quantum Chem. 116, 1532 (2016).

[3] (a) F. Lipparini, C. Cappelli. V. Barone, J. Chem. Theory Comput., 8, 4153 (2012); (b) F. Lipparini, C. Cappelli, N. De Mitri, G. Scalmani, V. Barone, J. Chem. Theory Comput. 8, 4270 (2012); (c) F. Lipparini, C. Cappelli, V. Barone, J. Chem. Phys. 138, 234108 (2013); (d) M. Caricato, F. Lipparini, G. Scalmani, C. Cappelli, V. Barone J. Chem. Theory Comput. 9, 3035 (2013); (e) I. Carnimeo, C. Cappelli, V. Barone, J. Comput. Chem. 36, 2271 (2015).

[4] (a) F. Lipparini, F. Egidi, C. Cappelli, V. Barone, J. Chem. Theory Comput. 9, 1880 (2013); (b) F. Egidi, I. Carnimeo, C. Cappelli, Opt. Mater. Express 5, 196 (2015); (c) F. Egidi, R. Russo, I. Carnimeo, A. D’Urso, G. Mancini, C. Cappelli, J. Phys. Chem. A 119, 5396 (2015); (d) T. Giovannini, M. Olszowka, C. Cappelli, J. Chem. Theory Comput. 12, 5483 (2016).

Two-dimensional Electronic Spectroscopy from the Visible to the Ultraviolet Giulio Cerullo

Dipartimento di Fisica, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano, Italy [email protected]

Nuclear Magnetic Resonance (NMR) is a diagnostic technique that has revolutionized structural biology, allowing to determine complex molecular structures with high spatial resolution. In two-dimensional (2D) NMR the signal is recorded as a function of two time variables and the data are Fourier transformed twice to yield a spectrum which is a function of two frequency variables. A wealth of novel information on molecular structure and dynamics can be obtained by extrapolating these 2D techniques to the optical domain, using femtosecond light pulses [1]. 2D spectroscopy is the “ultimate” ultrafast optical experiment, since it provides the maximum amount of information that can be extracted from a system within third-order nonlinear spectroscopy. The first applications were with IR pulses, resonant with vibrational transitions. Recently, 2D optical techniques have been extended to the visible and UV ranges, targeting electronic transitions. 2D electronic spectroscopy (2DES) allows fundamentally new insights into the structure and dynamics of multi-chromophore systems, measuring how the electronic states of molecules within a complex interact with one another and transfer electronic excitations [2]. By spreading the information content of the nonlinear signal on two frequency axes, 2DES allows: (i) to measure the homogeneous linewidths of optical transitions, enabling to single out the individual levels in strongly congested spectra; (ii) to separate contributions to the nonlinear signal that are spectrally overlapped in the 1D experiments; (iii) to overcome the Fourier limit and to obtain simultaneously high temporal and spectral resolution; (iv) to directly observe and quantify couplings between different excited states, which appear as cross peaks in the 2D spectra; (v) to follow in real time the pathways by which the coupled electronic/nuclear dynamics within a complex multi-chromophoric systems evolve after photoexcitation, and to track energy/charge transfer processes. This presentation will review the experimental techniques currently used to perform 2DES in the visible range and we will present our approach to 2DES, based on a passive birefringent interferometer for the generation of phase-locked pump pulses [3]. We will present a few exemplary results on multi-chromophoric systems and nanostructures [4-6] and finally discuss the prospects of extending 2D techniques to the UV range, of interest for biomolecules such as DNA and proteins.

Figure 1 Scheme of pulse sequence used in a 2DES experiment. LO: local oscillator.

References [1] S. Mukamel, Annu. Rev. Phys. Chem. 51(2000) 691. [2] T. Brixner et al., Nature 434 (2005) 625. [3] D. Brida, C. Manzoni, and G. Cerullo, Opt. Lett. 37 (2012) 3027. [4] T. Stoll et al., J. Am. Chem. Soc. 138 (2016) 1788. [5] A. De Sio et al., Nature Commun. 7 (2016) 13742. [6] T. Stoll et al., J. Phys. Chem. Lett. 8 (2017) 2285.

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Theoretical Prediction of Resonance Raman and Resonance Raman Optical Activity Spectra

James R. Cheeseman1 1 Gaussian, Inc., Wallingford, CT, USA

[email protected]

Raman optical activity (ROA), the difference in Raman scattering intensity for left and right circularly polarized light, is a powerful tool for studying chiral molecules and determining the structure of biomolecules in their native environment. Raman optical activity spectra obtained from ab initio quantum chemical calculations, using the far-from-resonance approximation (FFR), can often enhance the interpretation of the experimental spectra. The FFR approximation is, however, no longer valid when the incident laser frequency becomes close to the energy of an electronic excited state. In this contribution, I will present a fully analytic derivative extension of a method, first introduced by Jensen and co-workers [1], to compute the resonance vibrational Raman (RR) and Raman optical activity (RROA) of molecules using density functional theory. In this approach, an imaginary empirical damping parameter, corresponding to an effective inverse lifetime of the excited states, is added to the incident frequency. The formalism is the same as the FFR case except the frequency-dependent mixed polarizability tensors and their respective geometric derivatives become complex. The additional work required to handle the complex case increases the computational cost by less than a factor of two. Additionally, this approach is compatible with the “two-step” procedure in which the force field and Raman/ROA tensors are computed in separate steps, thus allowing for the use of different levels of theory for each step [2]. Preliminary results suggest that this approximate method recovers a significant amount of the resonance effects as the incident frequency approaches an electronic excitation and compares well with vibronic methods when the excited state geometry is similar to the ground state geometry. In the case of a strong resonance with a single electronic state, the calculated RROA obtained using this method is monosignate with the same relative intensities as the parent Raman spectrum, as predicted and observed by Nafie [3-4].

References [1] L. Jensen, J. Autschbach, M. Krykunov and G. Schatz, J. Chem. Phys. 127. (2007). 134101.

[2] J. Cheeseman and M. Frisch, J. Chem. Theory Comput. 7. (2011). 3323.

[3] L. Nafie, Chem. Phys. 205. (1996). 309.

[4] M. Vargek, T. Freedman, E. Lee and L. Nafie, Chem. Phys. Lett., 287. (1998). 359.

Ab-initio Modelling of Molecular Motion Under Confinement María Pilar de Lara-Castells1, Andreas W. Hauser,2 Alexander O. Mitrushchenkov3

1Consejo Superior de Investigaciones Científicas, Madrid, 28006, Spain. 2Graz University of Technology, Graz, 8010, Austria.

3Paris-Est University, Paris, 77454, France.

[email protected]

This talk is dedicated to present our ab-initio modelling of molecular motion under confinement in two

different scenarios. The fundamental question addressed in the first part of my talk is if the superfluid phase existing in

helium droplets is a possible liquid medium for probing a long-range electron transfer or harpoon-typereaction since two antagonistic effects play an important role: On one hand, the molecular reactant species

are expected to move below the so-called critical Landau velocity, with its low value (57 m/s) favoringthe electron hopping process. On the other hand, the extrusion of helium upon the approach of the two

reactant species is expected to add an energetic barrier at the crossing region, quenching the harpooningprocess. To model it, we combine ab initio determinations of electronic couplings and interaction energies

in the relevant electronic states with a new concept of solvation-modified reaction pathways. The result isthe presentation of clear evidences of the occurence of the harpoon-type electron transfer [1], nicely

confirming recent experimental measurements [2]. The second part of my talk focusses on the modelling of quantum confinement of molecular motion

in carbon nanotubes [3,4]. Their high-surface areas and precisely tuned pores make them potentiallyuseful for applications such as gas adsorption, the selective separation of light isotopes, and as

nanoreactors. The role of quantum nuclear effects in molecular motion under confinement in carbonnanotubes is of fundamental interest, specially when dealing with light species at low temperatures. To

model the system, our methodological protocol combines DFT-based symmetry-adapted perturbationtheory, which we use to derive parameters for a new pairwise potential model describing the gas

adsorption to the carbon material, with an adsorbate wave function-based approach characterizingaccurately the quantum nuclear motion [3]. As applications, we will show how the dimensionality of

molecular confinement is modified by the nanotube diameter, why a recent experiment indicates thatmore N2 molecules than helium atoms are adsorbed in narrow nanotubes [5], and what ab-initio evidences

are obtained for hexagonal close packing of molecular deuterium clusters (see figure, from [3]),confirming low-temperature neutron-diffraction-based experimental measurements [6].

[1] María Pilar de Lara-Castells, Andreas W. Hauser, and Alexander O. Mitrushchenkov, J. Phys. Chem. Lett. 8

(2017) 4284 (also see: Andreas W. Hauser & María Pilar de Lara-Castells, Phys. Chem. Chem. Phys. 19 (2017) 342).

[2] Michael Renzler et al., J. Chem. Phys. 145 (2016) 181101.

[3] Andreas W. Hauser, Alexander O. Mitrushchenkov, and María Pilar de Lara-Castells, J. Phys. Chem. C 121 (2017)

3807 (also see: Andreas W. Hauser & María Pilar de Lara-Castells, J. Phys. Chem. Lett. 7 (2016) 4929).

[4] María Pilar de Lara-Castells, Andreas W. Hauser, Alexander O. Mitrushchenkov, and R. Fernández-Perea, Phys.

Chem. Chem. Phys. 19 (2017) 28621.

[5] Tomonori Ohba. Sci. Rep. 6 (2016) 28992.

[6] Carlos Cabrillo, private communication, publication in preparation.

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The Algebraic Diagrammatic Construction - a versatile approach to excited electronic states, ionization potentials and electron affinities

Andreas Dreuw

Interdisciplinary Center for Scientific Computing, Ruprecht-Karls University, Im Neuenheimer Feld 205, 69120 Heidelberg City, Germany

The algebraic diagrammatic construction (ADC) scheme provides a series of ab initio methods for the calculation of excited, ionized or electron-attached states based on perturbation theory. In recent years, the second-order ADC(2) scheme has attracted attention in the computational chemistry community due to its reliable accuracy and reasonable computational effort in the calculation of predominantly singly-excited states. Owing to their size-consistency, ADC methods are suited for the investigation of large molecules. Their Hermitian structure in combination with the availability of the intermediate state representation (ISR) allows for straightforward computation of excited state properties.

In this talk, I will summarize our recent developments in the framework of ADC, which have all been implemented within the adcman module as part of the Q-Chem program package. These developments comprise ADC(3) for direct computation of excitation energies, ionization potentials and electron affinities of closed and open-shell molecules. The excitation ADC methods have also been adapted to exploit the spin-flip idea to study also ground-state multi-reference molecules, bond-breaking and conical intersections. For the treatment of core-excited states, the core-valence separation (CVS) approximation has also been applied to ADC making efficient CVS-ADC(2) and CVS-ADC(3) programs available. Nuclear excited state gradients are now also available at ADC(2) and ADC(3) level of theory. Environment models like polarizable continuum models and frozen-density embedding have also recently been realized. In addition to the calculation of excited state energies and properties, also an extensive set of density analysis tools are available ranging from standard population analysis tools up to advanced transition density matrix analyses.

New variational and quantum monte carlo methods for theprediction of vibrational spectra

Michael Frisch and Ireneusz Bulik 1Gaussian, Inc., 340 Quinnipiac St Bldg 40, Wallingford, CT 06492 USA

I will present a novel approach to variational calculations of vibrational wavefunctions which includes non-linear optimization of the internal coordinates used to define the basis functions.This approach provides significantly better accuracy for the ground state than VSCF methods based on normal modes, and provides a good description of excited states using very low-order configuration interaction.The resulting wavefunctions are of sufficient quality to be useful for importance sampling in vibrational quantum monte carlo calculations and new methods are presented which facilitate the use of these wavefunctions in QMC calculations of excited states.

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Modeling of isolated molecules: a joint computational-spectroscopic approach Cristina Puzzarini1

1 Dipartimento di Chimica “Giacomo Ciamician”, University of Bologna, Bologna, 40126, Italy. [email protected]

The prediction and interpretation of structural properties are the starting points for a deep understanding

of thermochemistry, kinetics and spectroscopic signatures of molecular systems. To give an example, a detailed knowledge of the conformational behavior of the main building blocks of biomolecules in the gas phase (i.e., without the perturbing effect of the environment) is a mandatory prerequisite toward the understanding of the role played by different interactions in determining the biological activity in terms of structure-activity relationships.

Focusing on molecular spectroscopy, there is a strong relationship between the experimental outcome and the electronic structure of the system under investigation. Therefore, spectroscopic techniques, in particular those exploited in the gas phase, are accurate sources for structural information. However, it is seldom straightforward to derive molecular structures from the experimental information because of difficulties in dealing with thermal and/or environmental effects. Instead, accurate equilibrium structures can be obtained from high-level quantum-chemical calculations, for instance, by making use of composite schemes based on the coupled-cluster techniques. However, for medium-to-large sized molecular systems, such computations are still very challenging, due to the unfavourable scaling of highly correlated levels of theory with the number of basis functions. An important step forward in this field has been provided by the interplay of theory and experiment, which paves the route toward the extension of accurate structural studies to systems larger than those treatable by experimental and quantum-chemical methods separately.

There are two joint theory-spectroscopy approaches that can be pursued. We might define them as a “top-down” approach and a “bottom-up” strategy. The first one relies on extracting from experimental outcomes the equilibrium structure details by using quantum-chemical computations for providing the missing information [1]. This is denoted as the semi-experimental approach [2]. The second one consists in verifying the computed equilibrium geometry by means of a comparison between calculated and experimental spectroscopic properties [3]. This approach is at the heart of computational spectroscopy.

Figure 1. The C5 and C7 conformers of N-acetyl-glycinamide as disclosed by rotational spectroscopy

References [1] M. Piccardo et al., J. Phys. Chem. A 119 (2015) 2058.

[2] M. Mendolicchio et al., J. Chem. Theory Comput. 13 (2017) 3060.

[3] C. Puzzarini et a., J. Phys. Chem. Lett. 5 (2014) 534.

Can we accurately predict mechanisms of enzymatic reactions?

Maria João Ramos

UCIBIO@REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua

do Campo Alegre s/n, 4169-007 Porto, Portugal We know that we can establish catalytic mechanisms of enzymatic reactions and, in doing so, explain the findings of experimentalists, but can we actually predict them? This talk is concerned with the computational needs that we come across to figure out results within computational enzymology. Calculations devised to study protein interactions and circumvent problems in some relevant systems will be reported as well as recent developments in the establishment of some catalytic mechanisms. We have resorted to QM/MM (1,2) as well as other calculations (3,4), in order to analyse the energetics of processes related to the systems under study and evaluate their feasibility according to the available experimental data. 1. Cerqueira, Gonzalez, Fernandes, Moura, Ramos, Acc. Chem. Res., 48, 2875, 2015 2. Neves, Fernandes, Ramos, PNAS, 114, E4724, 2017 3. Oliveira, Cerqueira, Fernandes, Ramos, JACS 133, 15496, 2011 4. Gesto, Cerqueira, Fernandes, Ramos, JACS 135, 7146, 2013

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New models for time resolved processes occurring in excited electronic states

Nadia Rega Department of Chemical Sciences, University of Napoli Federico II, Italy

e-mail: [email protected] The understanding at molecular level of photoinduced processes in condensed phase occurring on fast and ultrafast scale (femtoseconds to picoseconds) is one of the most fascinating challenge for theoretical chemistry. In this talk we discuss progress on going in our group regarding strategies to understand these phenomena, which are based on excited state ab-initio molecular dynamics simulations and a hybrid implicit/explicit model of solvation.[1,2] We present a time resolved vibrational analysis designed to follow transient vibrational dynamics extracted from excited state trajectories domain.[3-6] We also discuss the study of reactivity of photoacids in aqueous and non aqueous solvents.[7,8] We will focus on perspectives, limits and future challenges of these methods. References [1] S. Mukamel, Annu. Rev. Phys. Chem. 51(2000) 691. [2] N. Rega, G. Brancato, V. Barone, Chem. Phys. Lett. 442, 367, 4 (2006). [3] G. Brancato, N. Rega, V. Barone, J. Chem. Phys. 128, 144501, 14 (2008). [4] C.Torrence, G.P. Compo, Bull. Am. Meteor. Soc. 79, 61 (1998). [5] A.Petrone, G.Donati, P.Caruso, N.Rega, J. Am. Chem. Soc. 136, 14866 (2014). [6] N. Rega, Theoretical Chemistry Accounts 116, 347 (2006). [7] F. Han, W. Liu, C. Fang, Chem. Phys. 422, 204 (2013). [8] R. Simkovitch, S. Shomer, R. Gepshtein, D. Huppert, J. Phys. Chem. B 119, 2253 (2015).

Molecular dynamics-based enabling tools for drug design

Walter Rocchia

Italian Institute of Technology, Italy

The detection and characterization of binding pockets and allosteric communication in proteins is crucial for studying biological regulation and performing drug design. Nowadays, ever-longer molecular dynamics (MD) simulations are routinely used to investigate the spatiotemporal evolution of proteins. In this talk, I will describe a new tool, called Pocketron, that examines pocket formation, dynamics and allosteric communication embedded in microsecond-long MD simulations. Knowledge about cryptic and transient sites is instrumental for subsequent computational and/or experimental studies. Along these lines, we exemplify here the MD-Binding approach, which represents a fully dynamical docking tool that uses predefined target binding pocket for ligand screening.

Figure: Networks of the most persistent pockets found in two different isoforms of the Abl kinase protein in presence and absence of an allosteric binder. Each pocket (i.e. network node) is represented as a sphere, with the different colors indicating the pocket’s persistency. The pockets are connected via black lines (i.e. network edges). The width of each edge is proportional to the communication frequency.

G. La Sala, S. Decherchi, M. De Vivo, and W. Rocchia, “Allosteric Communication Networks in Proteins Revealed through Pocket Crosstalk Analysis”, ACS Central Science, 3 (9), 949-960, 2017

[email protected]

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The contribution of computational chemistry to chemo- and photodynamic therapies

Nino Russo

Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, I-87036 Rende, Italy

[email protected] The contribution of theoretical and computational chemistry in the field of chemo- and photodynamic cancer therapy will be presented and discussed. In particular, the discussion will be focused on the possibility to design new drug active in both chemo- and photo-dynamic therapy, by using density functional theory. Platinum II and IV compounds and the photophysical properties (absorption wavelengths, singlet-triplet energy gaps and spin-orbit matrix elements) of a series of photosensitizers will be presented.

References G. Mazzone, N. Russo, E. Sicilia, Can. J. Chem. 91(2013)902; M. E. Alberto, C. Iuga, A. D. Quartarolo, and N, Russo, J. Chem. Inf. Model., 53 (2013) 2334; M. E. Alberto, T. Marino, A. D. Quartarolo, N. Russo, Phys. Chem. Chem. Phys., 15 (2013)16167; A. D. Quartarolo, D. Pérusse, F. Dumoulin, N. Russo, E. Sicilia, J. Porphyrins Phthalocyanines, 17(2013) 980; M. E. Alberto, B. C. De Simone, G. Mazzone, A. D. Quartarolo, N. Russo, J. Chem. Theory Comput, 10 (2014) 4006; M. E. Alberto, G. Mazzone, A. D. Quartarolo, F. F. Ramos Sousa, E. Sicilia, N. Russo, J. of Comput. Chemistry 35 (2014) 2107; M. E. Alberto, B. C. De Simone, G. Mazzone, T. Marino, N. Russo, Dyes and Pigments, 120 (2015), 335; ] i. Ritacco, E. Sicilia, T. Shoeib, M. Korany, N. Russo, Inorg. Chem. 2015, 54, 7885; M, E. Alberto, B, C. De Simone, G, Mazzone, E, Sicilia, N. Russo, Phys. Chem. Chem. Phys., 17 (2015), 23595 – 23601; I. Ritacco, N. Russo, E. Sicilia, Inorg. Chem., 54 (2015), 10801 ; J. Pirillo, B. C. De Simone, N. Russo, Theor Chem Acc 135 (2016) 8; I. Ritacco, G. Mazzone, N. Russo, E. Sicilia, Inorg. Chem., 55 (2016), 1580.; J. Pirillo, G. Mazzone, N. Russo, L. Bertini J. Chem. Inf. Model, 57 (2017) 234; B. C. De Simone, G. Mazzone, J. Pirillo, N. Russo, E. Sicilia Phys. Chem. Chem. Phys., 19 (2017), 2530 ; I. Ritacco, M. Al Assy, M. K. Abd El-Rahman, S. Ashraf Fahmy, N. Russo, T. Shoeib, E. Sicilia, Inorg. Chem., 56 (2017), pp 6013; T. Marino, A. Parise, N. Russo, Phys. Chem. Chem. Phys., 19 (2017).

Modeling nonlinear and multidimensional spectroscopies in complex environments

Kenneth Ruud

Hylleraas Centre for Quantum Molecular Science, Department of Chemistry, University

of Tromsø – The Arctic University of Norway, 9037 Tromsø, Norway [email protected]

Multiphoton absorption, and two-photon absorption in particular, is gaining increasing attention due to their prospective use in a wide range of applications, such as photodynamic therapy, drug delivery and non-invasive bioimaging. Multiphoton processes display higher focality, but also lower absorption cross section than the corresponding one-photon processes. It is therefore important to maximize multiphoton absorption cross sections, both with respect to the magnitude and the tuning of absorption cross sections of natural chromophores, as well as to the design of new chromophores with large multiphoton absorption cross sections. Computational modeling can here play an important role.1

Biological systems are complex, and the reliable modeling of one- or multiphoton absorption processes requires multiscale models that can account for the most important electrostatic and dynamical effects. In this talk, I will discuss some of our recent results from theoretical studies of multiphoton absorption processes in biomolecular systems, with a focus on the use of polarizable embedding2 as a means of describing large biological systems. I will discuss the dependency of the computed multiphoton absorption cross sections on the size of the quantum region,3 local field effects, and multiphoton absorption from intermolecular charge-transfer excitations in biological systems.4 The perspectives for applying these methods to the study of multidimensional vibrational spectroscopies in complex environments will also be addressed. This will be discussed in the context of recent developments in our group on a general scheme for the identification of the relevant contributions to the spectroscopic process, implemented in the computer program Wilson. References [1] Helgaker, T.; Coriani, S.; Jørgensen, P.; Kristensen, K.; Olsen, J.; and Ruud, K. Chem. Rev. 112, 543-631 (2012). [2] Olsen, J. M. H.; Aidas, K.; Kongsted, J. J. Chem. Theory Comput. 6, 3721 (2010). [3] Steindal, A. H.; Beerepoot, M. T. P.; Ringholm, M.; List, N. H.; Ruud, K.; Kongsted, J.; Olsen; J. M. H. Phys. Chem. Chem. Phys. 18, 28339 (2016). [4] Beerepoot, M. T. P.; Friese, D. H.; Ruud, K. Phys. Chem. Chem. Phys. 16, 5968 (2014)

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Oral Presentations Oral Presentations


Tautomerism and proton transfer: when and if theory meets experimentLiudmil Antonov

Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia, BG-1113, [email protected]

Prototropic tautomerism [1] is one of the most important phenomena in organic chemistry despite the relatively small proportion of molecules in which it can occur. Tautomers are the chameleons of chemistry, capable of changing by a simple change of environment from an apparently established structure to another not perhaps till then suspected, then back again when the original conditions are restored, and of doing this in an instant: intriguing, disconcerting, perhaps at times exasperating. It therefore becomes vital to knowand/or to predict which tautomer is the major one, since not only structure but chemical properties are bound up with this. However, a real tautomeric equilibrium, from the viewpoint of classical spectrophotometric analysis,means Gibb’s free energy in the range roughly from -2 to +2 kcal/mol. In addition, the exact estimation of the ∆G values, in this particular case, requires isolated tautomeric forms as standards, a condition that isimpossible in most of the systems. Consequently, two challenges for the experiment and the theory are available when a tautomeric system is investigated: estimation of the proportion of the tautomers in the mixture and their optical spectra.A major breakthrough in the experimental studies was the development of chemometric methods [2] to obtain the absorption spectra of the individual tautomers, even though these are never present in their pure form, and to estimate the tautomeric constants as function of number of external parameters (temperature, irradiation, solvents, pH, and concentration). In this way, more or less, the problems are solved by the experiment.The availability of these experimental data has given the opportunity to check the quantum-chemical reliability in predicting tautomeric equilibria as function of the environment. There is development in predicting the absorption spectra. Does it mean that the tautomerism is not a challenge for quantum chemistry?A viewpoint of an experimentalist will be presented considering experimental results and theoretical description of several difficult tautomeric cases: molecular switches based on azonaphthols [3], tautomeric molecular motors [4], ground and excited state proton transfer in 10-hydroxybenzo[h]quinolines [5], and the tautomerism and solubility of curcumin in water [6]. And the problems which we, experimentalists, face when using quantum chemistry in these and similar cases, will be outlined to give an impulse for further development.

References[1] P. G. Taylor, G. van der Zwan, and L. Antonov, Tautomerims: Methods and Theories, edited by L. Antonov

(Wiley-VCH, Weinheim, 2015) 1-24.

[2] L. Antonov, and D. Nedeltcheva, Chem. Soc. Rev. 29 (2000) 217.

[3] L. Antonov et al. ChemPhysChem 16 (2015) 649.

[4] S. Hrisotva et al. Dyes and Pigments 144 (2017) 249.

[5] H. Marciniak et al. Phys. Chem. Chem. Phys. 19 (2017) 26621.

[6] Y. Manolova et al. Spectrochim. Acta 132A (2015) 815.

Vibrational Density Matrix Renormalization Group (vDMRG) Alberto Baiardi1, Christopher J. Stein2, Vincenzo Barone1 and Markus Reiher2

1 Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126, Pisa, Italy. 2 ETH Zürich, Vladimir-Prelog-Weg, 8093, Zürich, Switzerland.

e-mail [email protected]

Vibrational spectroscopy is a valuable tool for the characterization of molecular systems. Different spectroscopic techniques (such as IR absorption, vibrational circular dichroism, Raman scattering) are usually combined to fully characterize the target system. In order to decode the detailed information of an experimental spectrum of a complex molecular system, simple selection rules based on the harmonic approximation are usually insufficient, and the inclusion of anharmonic effects is mandatory [1]. In broad terms, the computational approaches currently in use for computing vibrational spectra at the anharmonic level can be divided in two main classes, perturbative and variational. Methods belonging to the former class, such as vibrational second-order perturbation theory (VPT2) [2-3], are particularly appealing for the study of semi-rigid systems, due to their favorable computational scaling. However, they are usually ill-suited for flexible systems, characterized by low-frequency, large-amplitude modes. For highly-flexible systems, more accurate results are obtained with variational methods, where vibrational energies are obtained by direct diagonalization of the vibrational Hamiltonian in a predetermined basis set. Their unfavorable scaling limits however their application to small molecules, with only few vibrational modes. A possible solution to this problem is offered by the density matrix renormalization group (DMRG) algorithm [4-5]. In the present contribution, we demonstrate how DMRG can be exploited to optimize vibrational wave functions expressed as matrix product states (MPSs). The resulting algorithm will be referred to as vibrational DMRG (vDMRG) [6]. The convergence of vDMRG calculations with respect to all the relevant parameter will be discussed, and possible strategies to improve its efficiency will be presented. Particular care will be paid to the difference between vDMRG and its electronic structure parallel. The standard formulation of vDMRG allows to optimize only ground states, thus providing zero-point vibrational energies (ZPVEs). The latter quantities are however of little interest in the simulation of vibrational spectra, in which the position and intensity of the bands is determined by vibrational excited states as well. To target also excited states, several energy-specific formulations of vDMRG, based on shift-and-invert techniques and root-homing algorithms, will be presented [7]. Moreover, the coupling of vDMRG with stochastic algorithms to reconstruct MPSs in terms of the harmonic basis functions will be presented. The reliability of the vDMRG will be shown for several molecules. First of all, the performance of vDMRG will be compared with those of other variational approaches available in the literature for small- and medium-size molecules. The algorithm will then be applied to the calculation of vibrational properties of large-size, biologically-relevant systems, whose study is challenging with standard variational approaches. References [1] V. Barone, M. Biczysko, J. Bloino, Phys. Chem. Chem. Phys. 16. (2014). 1759.

[2] J. Bloino, V. Barone, J. Chem. Phys. 136 (2012). 124108.

[3] J. Bloino, A. Baiardi, M. Biczysko, Int. J. Quantum. Chem. 116. (2016). 1543.

[4] U. Schollwöck, Ann. of Phys. 326. (2011). 96.

[5] Stefan Knecht, Erik Donovan Hedegård, Sebastian Keller, Arseny Kovyrshin, Yingjin Ma, Andrea Muolo, Christopher J Stein, Markus Reiher, CHIMIA International Journal for Chemistry 70. (2016). 244.

[6] A. Baiardi, C.J. Stein, V. Barone, M. Reiher, Journal of Chemical Theory and Computation 13. (2017). 3764.

[7] A. Baiardi, C.J. Stein, V. Barone, M. Reiher, in preparation

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Wavelet Transform for Spectroscopic Analysis Marco Pagliai1 and Gianni Cardini1

1Dipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, via della Lastruccia 3, Sesto Fiorentino (FI), 50019, Italy.

[email protected]

Vibrational spectra in condensed phases are strongly related to the local structure and inter-molecular interactions in the system and their interpretation relies on computational techniques. Molecular Dynamics (MD) simulations [1] are a useful computational approach to investigate a system at the same thermodynamic conditions of the experiments, taking into account the full anharmonicity of the chosen potential model. The method usually adopted to extract spectral features from MD trajectories is based on linear response theory. This approach gives a time averaged spectrum, as obtained experimentally in vibrational spectroscopy. All the information on the relation between instantaneous structure and spectral feature of the system is lost. A tool to localize a signal in time and frequency domain is needed to understand the strict relation between structural and spectroscopic properties of the system. A few techniques are available to solve this problem. Wavelet analysis methods [2, 3] have been shown to be one of the most reliable method to extract the time evolution of vibrational spectra from MD trajectories [4, 5].

References [1] M. P. Allen and D. J. Tildesley, Computer Simulation of Liquids, Oxford University Press, Oxford (UK), 2017.

[2] D. B. Percival and A. T. Walden, Wavelet Methods for Time Series Analysis, Cambridge University Press, Cambridge (UK), 2000.

[3] J. F. Kirby, Comput. Geosci. 31 (2005) 846.

[4] M. Pagliai, F. Muniz-Miranda, G. Cardini, R. Righini and V. Schettino, J. Phys. Chem. Lett. 1 (2010) 2951.

[5] F. Muniz-Miranda, M. Pagliai, G. Cardini and V. Schettino, J. Chem. Theory Comput. 7 (2011) 1109.

Binding free energies of host-guest systems by nonequilibrium alchemicalsimulations with constrained dynamics

E. Giovannelli1, M. Cioni1, P. Procacci1, G. Cardini1, M. Pagliai1, V. Volkov2, R. Chelli1

1Dipartimento di Chimica, Università di Firenze, Via della Lastruccia 3, 50019 Sesto F.no, Italy 2Interdisciplinary Biomedical Research Center, Nottingham Trent University, Nottingham, UK

e-mail: [email protected]

The fast-switching decoupling method is a powerful nonequilibrium technique to compute absolute binding free energies of ligand-receptor complexes [1]. Inspired by the theory of noncovalent binding association of Gilson and coworkers [2], we have developed two approaches, termed binded-domain and single-point alchemical-path schemes, based on the possibility of performing alchemical trajectories during which the ligand is constrained to fixed positions relative to the receptor. Validation of the two approaches is provided by comparing binding free-energy data relative to a Zn(II)·anion complex with those recovered from an alternative approach, based on steered molecular dynamics simulations. We also illustrate the method estimating absolute binding free energies of 1:1 complexes of β-cyclodextrin with benzene and naphthalene.

Figure 1 Thermodynamic cycle for computing absolute binding free energies through alchemical transformations.

References[1] R. B. Sandberg et al., J. Chem. Theory Comput. 11 (2014) 423. [2] M. K. Gilson et al., Biophys. J. 72 (1997) 1047.

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Parameterization of non-bonded models of metal ions using statistical learning techniques

Gianluca Del Frate1, Francesco Fracchia1, Giordano Mancini1, Walter Rocchia2 and Vincenzo Barone1

1 Scuola Normale Superiore, Piazza dei Cavalieri 7, Pisa, Italy

2 Department of Drug Discovery and Development, Istituto Italiano di Tecnologia, 16163 Genova, Italy

[email protected]

An accurate modeling of metal ions is of great importance to properly describe the related physicochemical properties from a computational point of view. Break of water structure and catalytic activity within protein sites are just a few of the primary roles acted by metal ions in chemical and biological processes [1,2]. In Molecular Dynamics (MD) simulations, metal ions are commonly described using non-bonded models, which rely on the classical Lennard-Jones plus Coulomb potentials. The van der Waals parameters (σ and ε) are determined in water, by reproducing experimental quantities (as the hydration free energy and the ion-water oxygen distance) [3,4]. However, the same parameters may be unsuitable for the classical modeling of the same species in more complex systems (e.g., proteins), and a transition to more sophisticated functional forms may be necessary [5]. In this work [6], a novel procedure (called LRR-DE) aimed at the optimization of non-bonded models for metal ions in soft matter is presented. The proposed method exploits the linear ridge regression (LRR) technique to optimize the linear parameters of a tunable model, and the differential evolution (DE) algorithm to refine the non-linear parameters, using the minimization of the leave-one-out cross-validation error as a criterion. Wide freedom in the choice of the functional form to be used is therefore allowed. Atomic forces and energies computed at the Density Functional Theory (DFT) level on model systems are used as output reference data. The method is validated by optimizing the non-bonded force fields of five metal ions (Zn2+, Ni2+, Mg2+, Ca2+, and Na+) in water as test cases. Beside the standard Lennard-Jones plus Coulomb functional, a more complicated and flexible form is parameterized to highlight the potentiality of the LRR-DE method for optimizing models of general functional forms. The performances of the new models in reproducing thermodynamic and structural properties from MD simulations are of comparable or better quality respect to available literature ones. References [1] Y. Marcus, Chem. Rev. 109 (2009) 1346

[2] Y. Miller, B. Ma, and R. Nussinov, PNAS, 107 (2010) 9490

[3] C. S. Babu and C. Lim, J. Phys. Chem. A, 110 (2006) 691

[4] P. Li, B. P. Roberts, D. K. Chakravorty, and K. M. R. Merz, J. Chem. Theory Comput., 9 (2013) 2733

[5] R. Wu, Z. Lu, Z. Cao, and Y. Zhang, J. Chem. Theory Comput., 7 (2011) 433

[6] F. Fracchia, G. Del Frate, G. Mancini, W. Rocchia, and V. Barone, J. Chem. Theory Comput., (2017) in press

Combining Molecular Dynamics and the Perturbed Matrix Method to study

Tyrosine UV-Vis spectroscopic properties

Sara Del Galdo1, Oliver Carrillo-Parramon1, Massimiliano Aschi2, Giordano Mancini1,4,

Andrea Amadei3 and Vincenzo Barone1,4

1 Scuola Normale Superiore di Pisa, Pisa, 56126, Italia. 2 Università di L’Aquila, L’Aquila, 67100, Italia.

3 Università di Roma Tor Vergata, Roma, 00100, Italia.4Istituto Nazionale di Fisica Nucleare (INFN) sezione di Pisa, Pisa, 56127, Italia.

e-mail: [email protected]

The Perturbed Matrix Method (PMM) is a robust and well-tested method to combine Molecular

Mechanics and Quantum Mechanics approaches to investigate quantum mechanical processes in complex

systems in condensed phases [1]. Similarly to other QM/MM methods, PMM is based on the definition of

a portion of the system to be treated at quantum mechanical level (the Quantum Center, or QC), interacting

with the rest of the system (the environment) described at classical atomistic level. This approach has been

very recently implemented with additional features in a general code to provide a user-friendly

computational tool [2].

In this study, we theoretically reproduced the UV-Vis absorption spectrum of aqueous solution of the

Tyrosine amino acid in zwitterionic form, by applying the PMM in conjunction with Molecular Dynamics

(MD) simulations. To achieve a better accuracy in the MD sampling, the Tyrosine Force Field (FF) was

parameterized de novo by deriving all the FF parameters from quantum mechanical calculations, following

the procedure implemented in the JOYCE software [3,4]. The comparison between our theoretical-

computational results and experimental data ensured that the model used captures the essential features of

the spectroscopic process. The results encourage the application of this methodology to study the electronic

spectroscopy of Tyrosine in protein, possibly exploiting the amino acid chromophoric properties for

probing protein structure, dynamics and interactions [5].

References

[1] M. Aschi, R. Spezia, A. Di Nola and A. Amadei, Chem. Phys. Lett. (2001) 374.

[2] O. Carrillo et al. J. Chem. Theory Compu. (2017), doi: 10.1021/acs.jctc.7b00341.

[3] V. Barone et al., Phys. Chem. Chem. Phys. (2013) 3736.

[4] V. Barone et al., Biopolymers (Under Revision)

[5] J. M. Antosiewicz and D. Shugar, Biophys. Rev. (2016) 163.

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Toward the Accurate Simulation of Vibrationally-Resolved Spectrafor Spin-Forbidden Transitions

Franco Egidi1, Marco Fusè1, Julien Bloino2, Alberto Baiardi1, Vincenzo Barone11 Scuola Normale Superiore, Pisa, 56126, Italy.

2 Consiglio Nazionale delle Ricerche, Istituto di Chimica dei Composti OrganoMetallici (ICCOM-CNR), Pisa, 56124, Italy.

[email protected]

Computational spectroscopy is routinely used as a predictive and interpretative tool to complement and support experimental results, provided the calculated results reach a sufficient level of accuracy. In this contribution, we present some of our recent developments for the simulation of vibrationally resolved electronic (vibronic) spectra for medium-to-large molecules, going beyond the simple Franck-Condon approximation [1]. In particular, we focus on transitions between states of different spin-multiplicity, which are forbidden under non-relativistic conditions [2]. The transition moments between such states cannot be obtained directly from most standard electronic structure calculations and a more accurate definition of the electronic Hamiltonian, including spin-orbit couplings, is needed [3]. Thanks to recent developments in non-collinear spin Density Functional Theory (DFT) [4,6], scalar relativistic effects and spin-orbit couplings can be included within the electronic Hamiltonian variationally. Excited states and electronic transition energies and property moments can then be evaluated using two-component Time-Dependent DFT (2c-TDDFT) [5,6]. Furthermore, it is possible to go beyond the Franck-Condon approximation and obtain more accurate band-shapes by numerically differentiating the transition property moments, which are responsible for Herzberg-Teller effects. As an illustration of those aspects, the vibronic spectra of organic systems as well as transition metal complexes can be simulated to study their photophysical properties as phosphorescent systems. The research leading to some of these results has been performed in the framework of the ERC Advanced Grant Project DREAMS “Development of a Research Environment for Advanced Modelling of Soft Matter”, GA No. 320951.

References[1] J. Bloino, A. Baiardi and M. Biczysko, Int. J. Quantum Chem. 116 (2016) 1543.[2] G. Baryshnikov, B. Minaev and Hans Ågren, Chem. Rev. 117, 6500 (2017).[3] T. Saue, ChemPhysChem 12 (2011) 3077.[4] G. Scalmani, M. J. Frisch, J. Chem. Theory Comput. 8 (2012) 2193.[5] F. Egidi, J. J. Goings, M. J. Frisch, X. Li, J. Chem. Theory Comput. 12 (2016) 3711.[6] F. Egidi, S. Sun, J. J. Goings, G. Scalmani, M. J. Frisch, X. Li, J. Chem. Theory Comput. 13 (2017) 2789.

Applications of Molecular Rotational Spectroscopy for Chiral Analysis Luca Evangelisti1 and Brooks H. Pate2

1 Department of Chemistry “G. Ciamician”, University of Bologna, Bologna, 40126, Italy. 2 Department of Chemistry, University of Virginia, Charlottesville, 22904, USA.

[email protected]

The introduction of three wave mixing techniques by Patterson, Schnell and Doyle [1,2] has expanded applications of molecular spectroscopy into the field of chiral analysis [3]. Chiral analysis is one of the most time consuming steps in the pharmaceutical industry. Current chromatography techniques can require significant measurement protocol development time, have high cost of consumables, and preclude the adoption of flow chemistry manufacturing principles [4] because they are too slow for real-time process control. There is particular interest in techniques that can routinely analyze molecules with multiple chiral centers – a class of molecules that makes up an increasingly large fraction of small drug pharmaceuticals. This work adapts a common strategy in chiral analysis to molecular rotational spectroscopy. A “chiral tag” is attached to the molecule of interest by making a weakly bound complex in a pulsed jet expansion. When this tag molecule is enantiopure, it will create diastereomeric complexes with the two enantiomers of the molecule being analyzed and these can be differentiated by molecule rotational spectroscopy. Identifying the structure of this complex, with knowledge of the absolute configuration of the tag, establishes the absolute configuration of the molecule of interest. Furthermore, the diastereomer complex spectra can be used to determine the enantiomeric excess of the sample (when the enantiopurity of the tag is known prior to measurement). The ability to perform chiral analysis using standard rotational spectroscopy instruments via the tag strategy will be illustrated by a study the example of the reaction products produced in the synthesis of Isopulegol from citronellal in the industrial production of menthol. The advantages and disadvantages of rotational spectroscopy over the current analytical methods such as gas chromatography and VCD will be presented. The possibility of using current methods of quantum chemistry to assign a specific structure to the chiral tag complex will be discussed. Finally, chiral tag rotational spectroscopy offers a “gold standard” method for determining the absolute configuration of the molecule through determination of the substitution structure of the complex. When this measurement is possible, rotational spectroscopy can deliver a quantitative three dimensional structure of the molecule with correct stereochemistry as the analysis

References [1] E. Hirota, Proc. Jpn. Acad. Ser. B 88 (2012) 120.

[2] D. Patterson, M. Schnell, J.M. Doyle, Nature 497 (2013). 475.

[3] S. Lobsiger, C. Perez, L. Evangelisti, K.K. Lehmann, B.H. Pate, J. Phys. Chem. Lett. 6 (2015) 196.

[4] A. Adamo et al., Science 352 (2016) 61.

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Vibrationally Resolved Electronic Spectra of Styryl Substituted Bodipys: Benchmark of New Computational Protocols for the Simulation

Mariagrazia Fortino1, Alfonso Pedone1 and Julien Bloino2

1 University of Modena e Reggio Emilia, Modena, 41125, Italy. 2 Consiglio Nazionale delle Ricerche Istituto di Chimica dei Composti OrganoMetallici, Pisa,

I-56124, Italy.

[email protected]

Borondipyrromethene (bodipy) is a class of extremely versatile fluorophores that have found several applications. The great popularity is especially due to their easy functionalization that allows to modify their spectroscopic properties, such as absorption/emission wavelengths and charge transfer [1]. A deeper understanding of the tuning of bodipy properties after functionalization is critical for interpreting experimental results.To better rationalize the information contained in the available experimental spectra, appropriate theoretical/computational models are needed. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) are the preferred quantum mechanical tools to model ground and excited states.We have computationally investigated the electronic spectra of two styryl substituted bodipy molecules, of technological interest, properly taking into account the vibronic aspects.In this contribution we report a comparison between the experimental available counterpart recorded in methanol and the vibronic spectra of two modified bodipy molecules computed by using both the time independent and the time dependent formalism, at harmonic level [2]. Moreover, with the aim to find a versatile computational protocol several exchange-correlation functionals have been benchmarked and also the possibility to extend the TI and TD evaluation of vibronic effects to various sets of internal coordinates has been considered and tasted with respect to experiments. In addition to these assessments, for the approximation of the transition dipole moment both Franck-Condon model and the extension proposed by Herzberg and Teller have been probed.

References [1] H. Lu, J. Mack, Y. Yang, Z. Shen, Chem. Soc. Rev. 43 (2014) 4778.

[2] J. Bloino, A. Baiardi, B. Malgorzata, Int. J. of Quant. Chem. 116. (2016) 1543.

Analysis of theoretical absorption and circular dichroism spectra of complex systems: the case of monolayer-protected clusters

Le Chang1,3, Oscar Baseggio2, Mauro Stener2 and Alessandro Fortunelli3

1 International Research Center for Soft Matter, Beijing 100029, China. 2 Dipartimento di Scienze Chimiche e Farmaceutiche, Un , Trieste 34127, Italy.

3 CNR-ICCOM, Consiglio Nazionale delle Ricerche, Pisa, 56124, Italy. e-mail address: [email protected]

We focus on the chiro-optical properties of a class of metal nanoclusters in which a metal core isprotected by a layer of coating ligands, typically thiol (RS-) ligands and gold (Au) as a metal but also considering selenium ligands (RSe-) and nano-alloys of Au and Ag. For a number of these monolayer-protected clusters (MPC) with precise chemical composition X-ray crystal structure has been determined,thus enabling studies of structure/property relationships at an unprecedented level. Despite the explosive research activity in this field, many are the yet unanswered questions, concerning both structural and electronic properties, resulting in a varied, only partially understood but very promising optical response [DOI: 10.1039/C5CP00498E]. Here we concentrate on the interplay of plasmonic vs. metal/ligand resonance features. We have shown that in MPC strong absorption peaks can be obtained that are related not to a classic metal surface plasmon but rather to an enhancement due to a resonance via electronic conjugation between damped metallic excitations and molecular-like features due aromatic ligands ("plasmon re-birth") [DOI: 10.1021/acs.jpclett.6b02810]. To better understand this phenomenon, we set up a palette of analysis tools of the chiro-optical response, featuring Individual Component Mapping (ICM), Oscillator Strength Density (OSD) and Rotatory Strength Density (RSD) plots, and fragmentation decomposition [DOI: 10.1021/acs.jpcc.6b12029], also exploiting a recently developed efficient TDDFT algorithm [DOI: 10.1002/qua.25175; 10.1021/acs.jpcc.6b04709; 10.1021/acs.jpcc.6b07323]). OSD/RSD and ICM are complementary tools to visualize and analyze chiro-optical response either in real space (OSD/RSD) or in the conjugate space of molecular orbitals, allowing one to single out the most important contributions in terms of single-particle excitations (ICM), while fragment projection enables one to analyze TDDFT absorption and (for the first time) CD spectra and achieve a rigorous decomposition of the TDDFT response into fragments, freely defined as chemical parts of the systems or functional basis sets in a general way (e.g. s/p and d bands). Through this analysis not only we disentangle plasmonic vs molecular-like contributions to absorption/CD spectra, but we also discover new sources of enhancement or depression of chiro-optical response in medium-size MPC, such as destructive or constructive interference, thus achieving an in-depth understanding which then turns into rationalization and design of chiro-optical plasmonic and molecular-like response of MPC species exhibiting optimal features.

Figure 1. 2D (left, middle) and 2D/3D (right) ICM plots of selected MPC.

34 35



Non-adiabatic dynamics on hybrid light-matter states J. Fregoni1,2, G. Granucci3, M. Persico3 and S. Corni2,4

1 University of Modena and Reggio Emilia, Modena, 41124 , Italy. 2CNR-Institute of Nanosciences, Modena, 41124, Italy.

3University of Pisa, Pisa, 56124, Italy. 4University of Padova, Padova, 35131, Italy.

[email protected]

The strong coupling regime, i.e. the coherent exchange of energy between matter and radiation in optical cavities, was initially modelled by Jaynes and Cummings [1]. Recent achievements of strong light-matter couplings [2] have unravelled a manyfold of exotic applications, ranging from enhanced optical response to quantum information, sensing and polaritonic chemistry [3]. The latter aims to study how the electronic states of molecules are modified by the coherent coupling of molecules with an electromagnetic field. The system potential energy surfaces are then described by the definition of hybrid light-matter states: the polaritons. The modulation of Polaritonic Potential Energy Surfaces (PoPESs) through light-matter coupling brings, in principle, the possibility to control the quantum yields of photochemical reactions, recently shown on model molecules [4]. Non-adiabatic dynamics (NAD) methods have been developed to simulate photochemical reactions extensively, providing a good starting point for polaritonic chemistry. In our work, we make a step toward the realistic description of azobenzene photoisomerization reaction on PoPESs. To this aim, we exploit a modified version of the Direct Trajectory Surface Hopping (DTSH)[5] method devised by Granucci, Persico and coworkers. Such method conjugates the low computational burden of a semiempirical description with a good level of accuracy provided by high-quality parametrization of the electronic hamiltonian. The results in the computation of PoPESs with an extended Jaynes-Cummings model and some examples of photoisomerization on polaritonic states are presented.

References 1. D. Craig and T. Thirunamachandran, Molecular Quantum Electrodynamics: An Introduction to Radiation-

molecule Interactions. Editor Academic Press (1984).

2. R. Chikkaraddy, B. De Nijs, F. Benz, S. J. Barrow, O. A. Scherman, E. Rosta, A. Demetriadou, P. Fox, O. Hess, J. Baumberg, Nature 535. (2016). 127.

3. J. Feist, J. Galego, and F. J. Garcia-Vidal, ACS Photonics (2017). A.

4. S. M. M. Kowalewski, K. Bennett, S. Mukamel, J. Phys. Chem. Lett. 7 (2016). 2050.

5. G. Granucci, M. Persico, A. Toniolo, J. Chem.Phys. 114 (2001). 24.

Chiral properties of transition metal complexes studied

through computational vibrational spectroscopy

Marco Fusè1, Julien Bloino2, Franco Egidi1, Alberto Baiardi1, Vincenzo Barone1

1Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy.2 Consiglio Nazionale delle Ricerche, Istituto di Chimica dei Composti OrganoMetallici

(ICCOM-CNR), UOS di Pisa, Via G. Moruzzi 1, 56124 Pisa, Italy.

[email protected]

Characterization of the chiral properties of a compound is central issue in several fields such as catalysis,

materials and life science. In the last years, vibrational analysis supported by Density Functional Theory

(DFT) calculations have had considerable successes in assigning the absolute configuration (AC) and

evaluating the conformational properties of many molecular systems. However, the harmonic

approximation, which is commonly used to simulate spectra, may be insufficient due to limitations in the

accuracy and lack of features caused by the missing contributions from overtones and combinations.

Thanks to the recent developments done in our group, it is now possible to simulate anharmonic spectra

with correction to both energies and intensities. In this contribution, we will show examples of accurate

simulation of IR and vibrational circular dichroism (VCD) spectra beyond the harmonic approximation

[1]. Nevertheless, due to the computational cost, in systems of medium-to-large size as the transition

metal complexes full anharmonic calculations can be very challenging. Therefore, an appealing

alternative is to reduce the dimension of the system to a set of normal modes directly involved in the

studied feature of the spectrum [2]. In this contribution, we will present some strategies for the careful

definition of the reduced dimensionality (RD) scheme helped by user-friendly interfaces.

Moreover, computations can provide extensive analysis on the origin of the band-shape and employing

graphical tools can significantly aid the understanding of these phenomena. For example, transition

current density (TCD) [3] maps, which allow an evaluation of the electron flow associated to the

molecular vibration, provide insights in the origin of the intensities, that are generally lost when only

numerical values are considered. All these aspects will be illustrated using the presented ad hoc tools

through a series of chiral ruthenium cyclopentadienyl carbonyl complexes, for which the carbonyl

stretching has been recently proposed as probe of the chirality at the metal center [4].

The research leading to these results has been performed in the framework of the ERC Advanced Grant Project

DREAMS “Development of a Research Environment for Advanced Modelling of Soft Matter”, GA No. 320951.

References

[1] J. Bloino, V. Barone, J. Chem. Phys. 136. (2012). 124108.

[2] H. Kvapilová, A. Vlček, V. Barone, M. Biczysko, S. Záliš, J. Phys. Chem. A 119. (2015). 10137–10146

[3] L. A. Nafie, J. Phys. Chem. A 101. (1997). 7826–7833.

[4] M. F. , G. Mazzeo, et al. , Chem. Commun. 51. (2015). 9385–9387.

36 37



User-friendly access to the Virtual Multifrequency SpectrometerDaniele Licari1 and Vincenzo Barone1

1 Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, [email protected]

How can we bring the computational spectroscopy from a strongly specialized research area to a general tool in the inventory of most researchers? What tools should be created to increase the interaction between experimentally oriented users and theoretically oriented developers?

In this contribution, we are going to answer these questions by presenting VMS-Draw [1]. It is a multi-platform graphical user interface (GUI), which provides the user with a powerful integrated environment for pre- and post- processing of quantum-chemical calculations (from NMR to UV spectroscopies) [2-4]and visualizing relevant information in an intuitive way. In addition, VMS-Draw includes a panel of advanced tools for the comparison of theoretical and experimental spectra, thus assisting their interpretation.

Figure 1 The preprocessing tools provides an interface for the automatic creation of the input files for the computational tools (VMS-Comp, SPFIT/SPCAT and SoSNMR). VMS Draw offers an interface for submitting and monitoring jobs on a cluster platform using an integrated PBS Client. In addition, it provides a powerful graphical environment for an intuitive interpretation of theoretical outcomes and a direct comparison to experiment.

References[1] D. licari et al., J. Comput. Chem. 36, (2015). 321

[2] V. Barone WIRES 6, 86 (2016).4.

[3] D. Presti, A. Pedone, D. Licari,V. Barone, J. Chem. Theor. Comp. (2017), 13(5), 2215-2229.

[4] D. Licari, N. Tasinato, L. Spada, C. Puzzarini, V. Barone, J. Chem. Theor. Comp. (2017),13(9), 4382-4396

From QM cluster to QM/MM ONIOM simulations:

the case of LigW-decarboxylaseMario Prejanò,1 Tiziana Marino1 and Nino Russo1

1 Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, cubo 14C, Ponte P. Bucci, 87036-Rende, Italy

[email protected]

Enzymes are the most proficient catalysts known on Earth, able to accelerate diverse chemical reactions by many orders of magnitude. Their extraordinary catalytic power is mainly ascribed to highly preorganized active sites, which properly position the catalytic machinery for efficient transition state stabilization. Understanding enzyme action is therefore of widespread importance in biology and not only. Computational enzymology plays an increasingly important role allowing to elucidate and present the complete and detailed mechanism of an enzymatic reaction, including the characterization of reaction intermediates and transition states from both structural and energetic points of view. Such an information is not accessible to no other single experiment.

QM ONIOM-1 ONIOM-2

Figure 1 Three different models used for the LigW decarboxylase enzyme

Stimulated by the recent experimental and theoretical works on the 5-carboxyvanillate (5-CV) decarboxylase (LigW) [1,2] we have undertaken the investigation of the microbial catabolic pathways of the 5-carboxyvanillate decarboxylase by applying different approaches based on Density Functional Theory (one all-QM cluster and two QM/MM) (see Figure 1). A comparison of the obtained energy profiles has been done as a function of the used approach. Furthermore, the performance of different pure, meta-, and hybrid density functionals has been evaluated.

Reference[1] A. Vladimirova, Y. Patskovsky, A. Fedorov, J. B. Bonanno, E. V. Fedorov, R. Toro, B. Hillerich, R.

D. Seidel, N. G. J. Richards, S, C. Almo, F. M. Raushel, J. Am. Chem. Soc. 2016, 138, 826-836.[2] X. Sheng, W. Zhu, J. Huddleston, D. Fen Xiang, F. M. Raushel, N. G. J. Richards, F. Himo ACS

Catal. 2017, 7, 4968−4974.

38 39



Modeling the electromechanical response of rubrene single crystals Micaela Matta1, Marco J. Pereira1, Sai M. Gali1, Damien Thuau1, Yoann Olivier2,

Alejandro Briseno3, Isabelle Dufour1, Cedric Ayela1, Guillaume Wantz1, Luca Muccioli1,4 1 UniversityofBordeaux,Talence,33405,France.

2University of Mons, Mons, 7000, Belgium. 3 University of Massachusetts, Amherst, 01003, Massachusetts, USA.

4 University of Bologna, Bologna, 40136, Italy. [email protected]

Stretchable and flexible organic electronics constitute the core elements for a variety of cutting-edge applications, ranging from mechanical sensors to wearable or biocompatible devices [1]. While a controlled response to mechanical deformation is at the basis of the operation of devices such as pressure sensors, flexibility is a key feature for many other applications such as foldable displays or photovoltaic panels, and most notably for all diagnostic devices interfaced with the human body [2]. The knowledge of the electromechanical response of organic semiconductors to external stresses is therefore not only interesting from a fundamental point of view, but also necessary for the development of real world applications. The common interpretation of the electrical response of organic semiconductor crystals to mechanical stress relies on the assumptions that (i) deformation affects charge mobility mostly along the strained direction, and (ii) compressive strain increases mobility via a reduction of intermolecular distances and the associated increase of electronic overlap, with tensile stress producing the opposite effect [3,4].

Here [5] we demonstrate how this interpretation is oversimplified, by means of multiscale modeling and experimental measurements employing an original configuration where a single crystal field effect transistor is assembled on top of a flexible polymeric cantilever. Our simulations not only predict accurately the mechanical properties of rubrene, but also reveal that uniaxial strain conditions can give rise to unusual responses, namely mobility hardly changing or even decreasing while compressing. Moreover, both calculations and experiments show that the electro-mechanical responses along the directions exhibiting higher mobility and closer packing are strongly coupled: if strain is applied along

one axis, mobility strongly varies also along the other axis. This microscopic understanding of the relation between structural and mobility variations is essential for the interpretation of electromechanical measurements for crystalline organic semiconductors, and for the rational design of electronic devices. References [1] S. Wagner and S. Bauer, MRS Bull. 37 (2012) 207.

[2] T. Someya, Z. Bao and G. G. Malliaras, Nature 540 (2016) 379.

[3] P. Heremans et al., Adv. Mater. 28 (2016) 4266.

[4] Y. Park et al., Chem. Mater. 29 (2017) 4072.

[5] M. Matta et al., Mater. Horiz. published online (2017) DOI 10.1039/C7MH00489C.

Figure 1 Multiscale modeling and experimental measurements highlight the strong coupling between mechanical stress and mobility along the two in-plane orthogonal crystalline directions in rubrene field effect transistors.

Polymer films with Aggregation Induced Emission: a new tool for optical sensing and energy harvesting

Giuseppe Iasilli1, Pierpaolo Minei2 and Andrea Pucci1 1 Department of Chemistry and Industrial Chemistry of the University of Pisa, Pisa, 56124, Italy.

2 NEST – Scuola Normale Superiore, Istituto Nanoscienze – CNR (CNR-NANO), Pisa, 56127 Italy.

[email protected]

In this work, the use of fluorophores with Aggregation-Induced Emission (AIE) features is discussed for application in materials science as probes for sensing and energy harvesting. Notably, AIE systems with donor–acceptor structure are also called Fluorescent Molecular Rotors (FMRs).[1] In FMRs, the AIE effect is often ascribed to a non-emissive twisted intramolecular charge transfer (TICT) state which occurs in solution, whereas in aggregates or in viscous media, transition from locally excited to TICT is inhibited. Those molecules have become rather popular in the last 5–10 years thanks to their easy applicability as non-mechanical viscosity sensors, tools for protein characterization, and local microviscosity imaging. In polymers, AIE and FMR fluorophores are promising candidates to overcome all the fluorescence deactivation pathways due to fluorophore aggregation. Their intense fluorescence emission helps in both sensing [2] and energy harvesting applications, thus enabling the development of high performance plastic devices. Fluorescence also plays a pivotal role in solar energy harvesting in luminescent solar concentrators (LSCs) [3]. In LSCs, sunlight penetrates the top surface of an inexpensive plastic or glass waveguide. This light is absorbed by luminescent molecules which are either embedded in the waveguide or applied in a separate layer on top or bottom of the waveguide. A fraction of the re-emitted light is trapped in the waveguide by total internal reflection and then collected at the edges of the device to produce electric power by means of photovoltaic cells even with a cloudy sky. We expect that these concepts assisted by sustainable routes may steer innovative, smart and intelligent materials to be used in the everyday life. References [1] J. Mei, N. L. C. Leung, R. T. K. Kwok, J. W. Y. Lam and B. Z. Tang, Chem. Rev. 115 (2015) 11718. [2] P. Minei, M. Koenig, A. Battisti, M. Ahmad, V. Barone, T. Torres, D. M. Guldi, G. Brancato, G. Bottari and A. Pucci, J. Mater. Chem. C 2 (2014) 9224. [3] F. De Nisi, R. Francischello, A. Battisti, A. Panniello, E. Fanizza, M. Striccoli, X. Gu, N. L. C. Leung, B. Z. Tang and A. Pucci, Materials Chemistry Frontiers 1 (2017) 1406.

40 41



Exploring ultrafast photodynamics in solution: a new theoretical challenge Umberto Raucci1, Nadia Rega 1,2

1 Department of Chemical Sciences, University Federico II of Napoli, Napoli, 80126, Italy 2 Italian Institute of Technology, IIT@CRIB Center for Advanced Biomaterials for Healthcare

Napoli, 80126, Italy [email protected]

Exploring ultrafast photodynamics in solution is a new challenge for modern spectroscopic and theoretical approaches. Indeed, light irradiation adds new dimensions to the conventional ground state chemistry. Basically, the strongly perturbed electronic structure, reached when molecules get excited, leads to a reactive behavior that ground state chemistry cannot achieve. In this way weak acids in the ground state can turn theirself in very strong photoacids upon the electronical excitation.[1] Unveiling at molecular level the complex aspects of Excited State Proton Transfer (ESPT) reactions, with solvent molecules acting as proton acceptor, is extremely difficult. A wide range of time scales affects the ESPT kinetics, going from the femtosecond (electron density redistribution of the chromophore) to the nanosecond (diffusion process after the reaction) scale.[1] Furthermore the reaction phase space is very complex, involving both the photoacid and solvent degrees of freedom.[1,2] The exploration of different time scales in a very complex reaction space represents the main challenge for the theoretical simulation of ESPT processes. What is more, theoretical approaches are called to handle at the same time both the electronic redistribution of the chromophore and the solvent relaxation around the proton transferring complex, finely modulating the kinetics and thermodynamics of the reaction.[3] In this contribution we took up this challenge, investigating the mechanism and driving forces of ESPT reactions by means of Time-Dependent Density Functional Theory based ab-initio molecular dynamics simulations. An effective hybrid implicit/explicit model of solvation, was adopted to consider in an explicit way the solvent coordinate in the ESPT process.[4] The solvation and photoreactivity of a super photoacid, named QCy9, was investigated in water and methanol solution, both in the ground and the excited state. More closely, QCy9 is a super photoacid, which exhibits a very large ESPT rate constant, kPT = 1 x 1013 s-1, the largest value reported in the literature so far. This constant is the same independently on the nature of the solvent (water or methanol).[1] The solvent configuration space at the ground electronic state was deeply investigated analyzing the hydrogen bond network around the acid group and the proton acceptor solvent molecule. Several configurations in the Franck-Condon region, describing an average solvation, were then chosen as starting points for the excited state dynamics. In any case the excited state evolution spontaneously leads to the proton transfer event, whose rate is strongly dependent from the hydrogen bond network around the proton acceptor solvent molecule. This is true both in water and methanol solution. Our calculations revealed that the explicit and polarizable representation at least of three solvation shells around the proton acceptor molecule is necessary to stabilize the solvated proton and allow its diffusion across the solution. Moreover the analysis of the solvent molecules motions in proximity of the reaction site confirmed that the ESPT event between the donor and the acceptor molecules is actually assisted by the oscillations of solvent molecules belonging to the first and second solvation shell of the accepting molecule. References [1]. R. Simkovitch, S. Shomer, R. Gepshtein, D. Huppert, J. Phys. Chem. B, 119, (2014), 2253 [2]. P. Cimino, U. Raucci, G. Donati, M.G. Chiariello, N. Rega, Theor. Chem. Acc., 135, (2016), 117 [3]. U. Raucci, M. Savarese, C. Adamo, I. Ciofini, N. Rega, J. Phys. Chem. B, 119, (2015), 2650 [4]. G. Brancato, N. Rega, V. Barone, J. Chem. Phys., 128, (2008), 144501

Exploiting Immersive Virtual Reality for the analysis of chemical bondingAndrea Salvadori1, Marco Fusè1, Giordano Mancini1,2, Sergio Rampino1

and Vincenzo Barone1,2

1 Scuola Normale Superiore, Pisa, 56126, Italy. 2 Istituto Nazionale di Fisica Nucleare (INFN) sezione di Pisa, Pisa, 56127, Italy.

[email protected]

Caffeine [1] is a new molecular viewer developed at the SMART Laboratory of Scuola Normale Superi-ore (SNS) specifically designed to exploit modern Immersive Virtual Reality (IVR) technologies. Caf-feine supports both standard desktop computers as well as IVR systems such as the CAVE theater in-stalled at SNS. During the talk, I will discuss the latest developments of the software, related to the design and implementation of a dedicated set of tools and numerical procedures for the immersive analysis of chemical bonding, by employing the so-called “natural orbital for chemical valence/charge displacement” (NOCV/CD) [2] analysis method. By exploiting the Caffeine software in CAVE-like installations, re-searchers are now able to observe at human scale how electrons rearrange upon bond formation and, at the same time, to perform numerical analysis on the visualized data.

References.[1] Salvadori, A., Del Frate, G., Pagliai, M., Mancini, G. and Barone, V., “Immersive virtual reality in computa-

tional chemistry: Applications to the analysis of QM and MM data”, International Journal of Quantum Chemis-try, 2016, DOI:10.1002/qua.25207

[2] Bistoni G, Rampino S, Tarantelli F, Belpassi L (2015) Charge-displacement analysis via natural orbitals for chemical valence: Charge transfer effects in coordination chemistry. J Chem Phys 142(8):084112 (9).

42 43



Formation mechanisms of prebiotic molecules in the interstellar medium

D. Skouteris1, F. Vazart1, V.Barone1, C. Puzzarini2 1 Scuola Normale Superiore, Pisa

2 University of Bologna [email protected]

The search for the origin of prebiotic species in space is an ongoing discipline of enormous interest in astrochemistry and in the study of the origin of life. It has been shown that essentially all biological macromolecules can be envisaged as forming from relatively simple precursors, such as formamide, which are relatively common in interstellar clouds (ISCs). Yet, the formation of formamide and other simple prebiotic molecules is difficult to explain in the harsh environments of ISCs, where very low temperatures and number densities prevail. Dedicated experimental approaches have been developed to address prebiotic molecules formation mechanisms, in which either the low temperature or the low number density regimes are reproduced. Nevertheless, for some specific cases, the experimental techniques are difficult (if not impossible) to apply. For this reason, we have started a systematic investigation by using high-level electronic structure calculations coupled with kinetics calculations to elucidate the mechanisms of formation of complex organic molecules (COMs) of prebiotic interest which cannot be addressed experimentally. The mechanisms discussed take place exclusively in the gas phase, starting from reactants which are relatively abundant in ISCs. The species discussed include formamide (a possible precursor of both aminoacids and nucleobases), glycolaldehyde (a prototype for sugars), acetic acid (a possible precursor of glycine) and formic acid.

Noncovalent Interactions and Internal Dynamics in Pyridine–Ammonia:

A Combined Quantum-Chemical and Microwave Spectroscopy Study Lorenzo Spada1,2, Nicola Tasinato1, Fanny Vazart1, Vincenzo Barone1, Walther Caminati2

and Cristina Puzzarini2 1 Scuola Normale Superiore, Pisa, 56126, Italy. 2 Università di Bologna, Bologna, 40126, Italy.

[email protected]

The 1:1 complex of ammonia with pyridine is characterized by using state-of-the-art quantum-chemical computations combined with pulsed-jet Fourier-transform microwave spectroscopy [1]. The computed potential energy landscape indicates the formation of a stable σ-type complex, which is confirmed experimentally: analysis of the rotational spectrum shows the presence of only one 1:1 pyridine–ammonia adduct. Each rotational transition is split into several components owing to the internal rotation of NH3 around its C3 axis and to the hyperfine structure of both 14N quadrupolar nuclei, thus providing unequivocal proof that the two molecules form a σ-type complex involving both a N−H⋅⋅⋅N and a C−H⋅⋅⋅N hydrogen bond. The dissociation energy (BSSE- and ZPE-corrected) is estimated to be 11.5 kJ mol−1. This work represents the first application of an accurate yet efficient computational scheme, designed for the investigation of small biomolecules, to a molecular cluster.

References [1] L. Spada, N. Tasinato, F. Vazart, V. Barone, W. Caminati and C. Puzzarini, Chem. Eur. J. 23 (2017) 4876.

44 45

Poster Poster


Force Field development: fitting on high level QM data

Ener

gy (k

J/mol

)

Luminescent solar concentrators (LSC)

a) promising solution in decreasing the cost per unit of power generated.

b) polymeric sheet (e.g., poly(methyl metaacrilate), PMMA) + appropriate photoactive species.

c) Active species - based on extended π-conjugated systems - able to absorb sunlight and re-emitting it with high efficiency at red-shifted wavelength. - stable from a chemical point of view - exhibit large Stoke shifts in order to avoid re-absorption losses.

d) Spectral features easily tunable from the visible to the near infrared.

Nor

mal

ized

Abs

orba

nce

λ (nm)

Prediction and interpretation of structural and spectroscopic properties

Popu

latio

n

Dihedral value

Popu

latio

n

Radius of gyration (nm)

Dihedral value

Dihedral value

Spectroscopic characterization of new sulfur-containing molecules for astrochemical purposes

Silvia Alessandrini1,2, Jürgen Gauss3 and Cristina Puzzarini2 1Scuola Normale Superiore, Pisa, I-56126, Italy.

2Alma Mater Studiorum – University of Bologna, Bologna, I-40126, Italy. 3Universität Mainz, Mainz, D-55099, Germany.

[email protected] This work aimed at characterizing S-containing molecules of astrochemical interest. Indeed, the chemistry of sulfur in the universe is partially unknown and a lack of sulfur compounds with respect to the observed elemental abundance of sulfur, has been pointed out [1]. In details, the molecules considered are members of the thiocumulenes family but also some protonated species of molecules already observed in space, like OCS. The identification of molecules in the universe is mainly based on the observation of their rotational transitions. However, the rotational spectra collected by radio telescopes and space probes are usually difficult to interpret due to the presence of numerous signals. Therefore, it is necessary to have very accurate simulations of the rotational spectra and this can only be achieved thanks to a close collaboration between computational and experimental rotational spectroscopy. For all the molecules considered, the rotational spectrum has been simulated based on the theoretical estimation of the corresponding rotational parameters. To this end, the molecules have been classified, based on their computational cost, in small-sized and medium-sized systems. The former group has been characterized following the methodology presented in [2]. In details, the composite scheme CCSD(T)/CBS(5,6)+core(cc-pCVQZ)+fT+fQ+ΔB0(cc-pCVQZ) has been used to compute the rotational constants of the vibrational ground state (B0), while the quartic and sextic centrifugal distortion constants have been computed at the CCSD(T)/cc-pCVQZ level. For larger systems, a lower level of theory had to be used, thus considering the CCSD(T)/CBS(T,Q)+core(cc-pCVTZ)+ΔB0(cc-pVTZ) composite scheme for B0, while the quartic and sextic centrifugal distortion constants have been computed at the CCSD(T)/cc-pVQZ level and CCSD(T)/cc-pVTZ level, respectively. The knowledge of the uncertainties affecting the predicted rotational transition frequencies is fundamental to guide experimental and astronomical observations. These uncertainties are mainly due to the error associated to the B0 value. While [2] provides an estimate of the accuracy in the case of small-sized systems only containing first-row elements, to understand the error due to the composite scheme proposed for medium-sized molecules and how this is affected by the presence of a second-row atom, a new benchmark study on the accuracy of rotational constants has been carried out. This study involved 15 different computational approaches applied to 15 molecules, for a total of 85 isotopologues. The computational approaches allowed us to investigate the convergence to the complete basis set limit for the CCSD(T) method, the contribution of correlating core electrons, and the impact of vibrational corrections on rotational constants. One important conclusion is that the estimated mean error for the composite scheme applied to medium-sized molecules is of 0.27%. To test the results of our benchmark study, the rotational spectrum of the CCS radical has been investigated. Our theoretical simulation guided the measurement of 26 new rotational transition frequencies in the range 340-690 GHz. The comparison between the computed and the experimentally determined B0 showed discrepancy, in relative terms, of 0.005%. The comparison for other molecular systems for which experimental data are available will be discussed to demonstrate the reliability and accuracy of the computational procedure presented. References [1] P. M. Woods, A. Occhiogrosso, S. Viti, Z. Kaňuchová, M. E. Palumbo and S. D. Price, Monthly Notices of the

Royal Astronomical Society, 450 (2015) 1256.

[2] C. Puzzarini, M. Heckert and J. Gauss, The Journal of Chemical Physics 128 (2008) 194108.

46 47

Poster Poster


The formation pathway of aminoacetonitrile in the interstellar medium Alice Balbi1, Dimitrios Skouteris1 Nicola Tasinato1 Cristina Puzzarini2 and Vincenzo

Barone1 1 Scuola Normale Superiore, Pisa, 56126, Italy.

2 Dipartimento di Chimica “Giacomo Ciamician” Università di Bologna, Bologna, 40126, Italy [email protected]

For many years the interstellar medium was considered to be too hostile for organic species. However, the detection of about 200 molecular species in interstellar or circumstellar environments has changed this view dramatically. In these species are included prebiotic molecules, such as methyl formate, acetic acid and glycolaldehyde so those discoveries have stimulated the debate about the origin of the building blocks of life in the universe. [1] Because of their extreme conditions (very low number density and temperatures less than 10 K, or even highly energized regions [2]) astronomical environments present an unusual chemistry with many species which are not observed on Earth, hence there is an active research trying to understand how these molecules may be formed starting from the elements and very simple small molecules formed in the early universe. For the determination of these formation pathways are needed thermochemical data of the involved molecules. If the reaction mechanism is known it is possible to make calculations concerning the kinetics of the reaction, e.g. through the Rice-Ramsperger-Kassel-Marcus (RRKM) theory, possibly combined with capture theory and master equation resolution. [3] Aminoacetonitrile is a simple organic compound containing both nitrile and amino groups. It is somewhat similar to the simplest amino acid, glycine. This makes it interesting in the field of astrochemistry as a prebiotic molecule. In 2008, aminoacetonitrile was discovered in the Large Molecule Heimat, a giant gas cloud near the galactic center in the constellation Sagittarius by the Max Planck Institute for Radio Astronomy. [4] This discovery is significant to the debate on whether glycine exists widely in the universe and can lead to interesting insights relative to the comprehension of the reactions linked with the origin of life. In this work, the formation pathway of aminoacetonitrile in the interstellar medium (ISM) is investigated, both from an energetic and kinetic point of view. References [1] V. Barone, M. Biczysko and C. Puzzarini, Acc. Chem. Res. 48 (2015), 1413.

[2] R. C. Fortenberry, Int. J. Quantum Chem. 117 (2017), 81.

[3] F. Vazart, D. Calderini, C. Puzzarini, D. Skouteris and V. Barone, J. Chem. Theory Comput. 12 (2016), 5385.

[4] A. Belloche et al., A&A 482 (2008) 179.

Rates of non-radiative decays of excited states using adiabatic and diabaticapproaches

S. Banerjee1, A. Baiardi1, J. Bloino2 and V. Barone1

1 Scuola Normale Superiore, Pisa, 56126, Italy.2 ICCOM-CNR, Pisa, 56124, Italy.

[email protected]

In this contribution, we illustrate an approach to study rates of non-radiative excited state decays leading

to quenching of fluorescence, which has been addressed in the framework of both adiabatic and diabaticelectronic states within the regime of Fermi's golden rule. Electronic structure calculations have been

performed at the level of density functional theory (DFT) and time-dependent DFT. For the vibroniccalculations, an approach based on time-dependent correlation functions has been used. This has the

advantage of studying the temperature dependence of the transition rates at a low computational cost. Theharmonic approximation has been used for treating the vibrations and mode mixing between the normal

modes of the two electronic states has been considered for most cases. The couplings between electronicstates have been considered both within and beyond the Franck-Condon approximation, depending on the

type of process studied. In addition to the two most common forms of radiation-less decays, namelyinternal conversion and intersystem crossing[1], excitation energy transfer between singlet and triplet

electronic states has also been investigated[2]. Solvent effects have been considered when necessary. Arecent dipole-quadrupole based diabatization approach of Truhlar and co-workers has been used to

calculate the diabatic couplings between electronic states, using the dipole moments and quadrupolemoments of the corresponding adiabatic states and the corresponding transition moments [3,4]. For systems

with considerably different dipole moments in the two states, the couplings can be reasonably estimatedfrom the dipole moments[3]. The rate can then be computed, considering also the vibronic contributions

using a time-dependent correlation function. The formalism has been used for studying non-radiative ratesof medium to large sized molecules, including rigid and flexible systems. For molecules (eg.

diamondoids) which find large-scale industrial applications owing to their strong fluorescence, it isessential to have the knowledge of non-radiative rates which act as quenchers of fluorescence, in order to

design artificial emitters.

References

[1] S. Banerjee, A. Baiardi, J. Bloino and V. Barone, JCTC 12 (2016) 774.

[2] S. Banerjee, A. Baiardi, J. Bloino and V. Barone, JCTC 12 (2016) 2357.

[3] A. Piserchia, S. Banerjee and V. Barone, JCTC (accepted).

[4] S. Banerjee, D. Skouteris and V. Barone, Proceedings of ICCSA 2017, Trieste, July 3-July 6, 2017, (2017) 328.

48 49

Poster Poster


Benchmark Analysis on the Performances of Segmented Polarization Consistent Basis Sets for Spectroscopic Applications

Rahma Boussessi1, Nicola Tasinato1, Andrea Pietropolli Charmet2, Paolo Stoppa2 and Vincenzo Barone1

1 Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa, Italy. 2 Università Ca’ Foscari Venezia, Dipartimento di Scienze Molecolari e Nanosistemi, Via Torino

155, I-30172 Mestre (Venezia), Italy. [email protected]

In a recent work, the performances of several model chemistries rooted into density functional theory

(DFT) in yielding reliable sextic centrifugal distortion constants have been systematically investigated for different density functional in conjunction with the correlation consistent Dunning’s basis sets as well as the SNSD and the N07 basis sets [1].

In this contribution, we present a DFT benchmark study on the convergence patterns of the sextic

centrifugal distortion constants for a set of semi-rigid organic compounds towards the Frank Jensen’s segmented polarization consistent [2] basis sets and the correlation consistent basis sets [3-5].

We performed the investigation on a set of three halomethanes (CH3F, CH2F2, CH2FCl) and three haloethenes (CHF=CHCl, CH2=CFCl, CF2=CFCl). Because of their role as atmospheric pollutants and greenhouse gases, over the years these compounds have been the subjects of several theoretical and experimental spectroscopic investigations.

We employed the B3LYP [6] and the double-hybrid B2PLYP [7] functionals in combination with the segmented polarization consistent basis sets pc-seg-n (n = 0, 1, 2, 3, 4), the Dunning’s (aug-)cc-pVTZ basis sets, as well as the m-aug-cc-pVTZ [8] and maug-cc-pVTZ-dH [9]. Additional calculations were carried out by using the B3LYP functional in conjunction with the SNSD [10] basis sets.

Our predicted values were compared to the available data published and the effects related to the size of basis sets are presented and discussed. The obtained results demonstrate that for these molecules the utilization of pc-seg-n basis sets, which are also computationally less expensive, is recommended respect to the aug-cc-pVXZ basis sets.

References [1] A. Pietropolli Charmet, P.Stoppa, N. Tasinato, S. Giorgianni, J. Mol. Sperctroc. 335 (2017) 117.

[2] F. Jensen, J. Chem.Theory Comput. 10 (2014) 1074.

[3] T.H. Dunning Jr., J. Chem. Phys. 90 (1989) 1007.

[4] D.E. Woon, T.H. Dunning Jr., J. Chem. Phys. 98 (1993) 1358.

[5] R.A. Kendall, T.H. Dunning Jr., R.J. Harrison, J. Chem. Phys. 96 (1992) 6796.

[6] D. Becke, J. Chem. Phys. 98 (1993) 5648.

[7] S. Grimme, J. Chem. Phys. 124 (2006) 034108.

[8] E. Papajak, H. R. Leverentz, J. Zheng, D. G. Truhlar, D.G. J. Chem. Theory Comput. 5 (2009) 1197.

[9] T. Fornaro, M. Biczysko, J. Bloino, V. Barone, Phys. Chem. Chem. Phys. 18 (2016) 8479.

[10] I. Carnimeo, C. Puzzarini, N. Tasinato, P. Stoppa, A. Pietropolli Charmet et al., J. Chem. Phys. 139 (2013) 074310.

Concerted iron transit mechanism through ferritin channel; insights from computational modeling.

Balasubramanian Chandramouli1,2, Giordano Mancini2,3, Vincenzo Barone2,31Compunet, Istituto Italiano di Tecnologia (IIT), Via Morego 30, I-16163 Genova, Italy.

2Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa, Italy. 3 Istituto Nazionale di Fisica Nucleare (INFN) sezione di Pisa, Largo Bruno Pontecorvo 3, I-

56127, Pisa, [email protected] / [email protected]

Ferritin, a ubiquitous protein present in most living organisms, plays an essential role in iron storage and recycling [1]. The 24 subunits protein self assembles into a spherical cage-like structure with an internal diameter of 8 nm, which can sequester ~4500 iron atoms as mineral ferrihydrite. Two types of channels, formed at intersections of three (C3) or four (C4) subunits, pierce the shell providing pathways that connect the cage interior to the exterior surface [2]. In vertebrates, the hydrophilic C3 channel, containing the highly conserved acidic residues, facilitates iron (Fe2+) entry into the internal cavity [3]. In the vast literature on ferritin function, mechanistic details on ferrous iron translocation are still not completely unveiled. Recently, we attempted via extensive molecular dynamics simulations and enhanced sampling techniques, to shed lights on the iron passage through ferritin C3 channel. The results provide intriguing details on a concerted transit mechanism that involves two Fe2+ ions inside the channel. Besides its biological role, ferritins have been widely exploited for the production of metal nanoparticles [4]. Hence, the current study encourages further investigations to explore the channel response also to other metal ions.

References

[1] E.C. Theil, R.K. Behera, T. Tosha, Coord. Chem. Rev. 257 (2013), 579.

[2] K. Honarmand Ebrahimi, P.-L. Hagedoorn, W.R. Hagen, Chem. Rev. 115 (2015), 295.

[3] T. Takahashi, S. Kuyucak, Biophys. J. 84 (2003), 2256.

[4] Z. Zhen, W. Tang, T. Todd, J. Xie, Expert Opin. Drug Deliv. 11 (2014), 1913.

50 51

Poster Poster


Exploring nuclear photorelaxation and photoreactivity by

excited state Ab-initio dynamics and time resolved vibrational analysis.

M. Gabriella Chiariello1, Nadia Rega1 1Department of Chemical Science, University of Napoli ‘Federico II’, Napoli, 80126, Italy

[email protected]

Understanding at atomistic level the mechanism of photoinduced chemical reactions in terms of electronic/nuclear motions responding to the external perturbation is a challenging task from both experimental and theoretical point of view. Time resolved vibrational spectroscopies, such as femtosecond stimulated Raman spectroscopy (FSRS) [1], were shown to be a very powerful tool to investigate and follow in real time the nuclear motion of photoexcited chromophores. The interpretation of the often complex experimental spectra can benefit from the employment of a theoretical-computational approach. In particular, ab-initio molecular dynamics methods allow to simulate and accurately reproduce the behaviour of chromophore in solution in both equilibrium and far for equilibrium regime, i.e. after the interaction with light [2,3]. The analysis of the signals extracted from dynamics allows to create a direct link electronic/nuclear structure and spectroscopic properties [2]. The present contribution is focused on the photoreactivity of pyranine [ 8-hydroxypyrene-1,3,6-trisulfonic acid] in water solution [4]. Pyranine is a popular photoacid molecule, upon irradiation with light an excited state proton transfer reaction (ESPT) takes place. We are interested in ultrafast reactivity, namely that occurring in the femtosecond to picosecond time scale. During this time pyranine shows a characteristic activation of low frequencies skeleton modes upon excitation that precedes the ESPT event [5]. We adopted an integrated computational approach including ab-initio molecular dynamics and time resolved vibrational analysis based on Wavelet Transform [2]. This latter allows us to localize any signal extracted from excited state trajectory in both time and frequency domain. In this way, we can follow the activation and relaxation of the key normal modes of the photoexcited pyranine, and to reproduce the reaction pathway before the reactive event itself.

References [1] R.R.Frontiera, R.A.Mathies, Laser & Photonics Reviews 5. (2011). 102.

[2] A.Petrone, G.Donati, P.Caruso, N.Rega, J.Am.Chem.Soc. 136. (2014). 14866.

[3] U.Raucci, M.Savarese, C.Adamo, I.Ciofini, N.Rega, J. Phys. Chem. B 119. (2015). 2650.

[4] W. Liu, F. Han, C. Smith, C. Fang, J. Phys. Chem. B 116. (2012). 10535.

[5] W.Liu, Y.Wang, L.Tang, B.G.Oscar, L. Zhu, C.Fang, Chemical Science 7. (2016). 5484.

Time-resolved vibrational analysis of model peptides in aqueous solution from ground state ab-initio molecular dynamics simulations

Federico Coppola1, Greta Donati1 and Nadia Rega1,2 1 Department of Chemical Sciences, University Federico II of Napoli, Napoli, 80126, Italy

2 Italian Institute of Technology, IIT@CRIB Center for Advanced Biomaterials for Healthcare Napoli, 80126, Italy

[email protected]

Advanced time resolved and non-linear vibrational spectroscopic techniques, such as time-resolved Fourier Transform Infrared, two-dimensional Infrared and Femtosecond Stimulated Raman Spectroscopy,[1,2] are powerful tools to characterize in detail the structure and the dynamics of molecular systems in condensed phase. Plenty of information is provided by interpreting trends in the time of vibrational features, which are subtle probes of structural motifs and reaction mechanisms. Indeed, the connection of the spectroscopic data with the structural and the dynamical features is far to be an easy task. The computational vibrational spectroscopy can provide a valuable support due to its predictive-interpretative character. However, standard techniques are aimed at the solution of the quantum vibrational problem, as alternative, very promising are those computational protocols based on the analysis of molecular dynamics simulations of large molecules in condensed phase and at finite temperature. In this contribution we present the development and the validation of a novel theoretical-computational method to perform time-resolved vibrational analysis on peptide benchmarks in aqueous solution. This method[3] is based on the Wavelet Transform[4] of suitable time dependent signals obtained through ab-initio molecular dynamics.[3,4] The Wavelet protocol, unlike the Fourier Transform, allows for the accurate localization in the time domain of a given vibrational band, thus monitoring frequency fluctuations, anharmonicity and vibrational modes coupling. We focused on three models presenting several vibrational fingerprints of peptides: the Methyl-2-Acetamidopropanoate,the trans-N-MethylAcetamide and the non-covalent dimer in both gas and explicit water phase.[5-9] Once sampled the AIMD trajectories in ground electronic state,[10,11] the time dependent signals were then Wavelet transformed to get generalized normal-modes and time-resolved vibrational spectra directly comparable to those provided from modern vibrational spectroscopies.[12,13] We were able to reproduce accurately many vibrational signatures of the systems, including the vibrational frequencies, the qualitative vibrational coupling, reproducing also the characteristic solvent-induced frequency shift. Importantly, we were able to interpret these features in terms of a clear correlation between structure and spectroscopic behavior. In conclusion, we obtained a very good agreement with both the experimental results and the data that is possible to calculate with standard approaches.[5-9]

References

[1] T. Hayashi, S. Mukamel, Journal of Molecular liquids, 141, (2008), 149

[2] D.R. Dietze, R.A. Mathies, ChemPhysChem, 17, (2016), 1224

[3] A. Petrone, G. Donati, P. Caruso, N. Rega, Journal of the American Chemical Society, 42, (2014), 14866

[4] C. Torrence, G.P. Compo, Bulletin of the American Meteorological Society, 79, (1998), 61

[5] I.V. Rubstov, J. Wang, R.M. Hochstrasser , Journal of Chemical Physics, 118, (2003), 7733

[6] J. Wang, R.M. Hochstrasser , Journal of Physical Chemistry B, 110, (2005), 3798

[7] H. Torii, Journal of Physical Chemistry Letters, 6, (2015), 727

[8] L. De Marco, M. Thamer, M. Reppert, A. Tokmakoff, Journal of Chemical Physics, 141, (2014), 034502

[9] M.P. Gaigeot, R. Vuilleumier, M. Sprik, D. Borgis, Journal of Chemical Theory and Computation, 1, (2005), 772

[10] N. Rega, S.S. Iyengar, G.A. Voth, H.B. Schlegel, T. Vreven, M.J. Frisch, Journal of Physical Chemistry B, 108,

(2004), 4210

[11] G. Brancato, N. Rega, V. Barone, Journal of Chemical Physics,128, (2008), 144501

[12] N. Rega, Theoretical Chemistry Account, 116, (2006), 347

[13] N.Rega, G. Brancato, A. Petrone, P. Caruso, V. Barone, Journal of Chemical Physics,134, (2011), 074504

52 53

Poster Poster


Extending molecular dynamics in Gaussian: state of art and new perspectives

Jacopo Lupi1, Vincenzo Barone1, Gianni Cardini2, Giordano Mancini1, Marco Pagliai2

1Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy2Dipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, Via della

Lastruccia 3, 50019 Sesto Fiorentino, Italy

[email protected]

Gaussian [1] is one of the most used computational chemistry software package in the world and the

stable release is actually Gaussian 16. While Gaussian quantum chemistry related abilities are well

known and developed since its birth, the Molecular Dynamics (MD) and Monte Carlo (MC) related tools

started to be implemented only more recently.

Currently, for what concerns MD simulations, Gaussian code can sample canonical ensemble (NVT)

with various thermostats: Andersen, Berendsen and stochastic velocity rescaling [2-4]. Regarding the

integrator, the code can resolve flexible molecules Newton equations of motion with a symplectic

integrator scheme (with Velocity-Verlet and up to 8th integration order). In order to enhance the sampling

rate of the system, the integrator can perform Velocity-Verlet scheme for planar trigonal rigid fragments

(water-like) using the SETTLE algorithm [5].

The main goal of the project is to develop and implement in Gaussian code new algorithms for general

purpose rigid body dynamics, namely the quaternion propagation one [6] and the SHAPE algorithm [7].

Both of them had shown a comparable, if not better, compatibility and efficiency compared to others rigid

body algorithms, for example SHAKE and LINCS [8-9].

References

[1] Gaussian 16, M. J. Frisch et al. Gaussian, Inc., Wallingford CT, 2016.

[2] H. C. Andersen, J. Chem. Phys. 4. (1980). 2384.

[3] H. J. C. Berendsen, J. P. M. Postma, W. F. van Gunsteren, A. R. DiNola, J. R. Haak, J. Chem. Phys. 81.

(1984). 3684.

[4] G. Bussi, D. Donadio, M. Parrinello, J. Chem. Phys. 126. (2007). 014101.

[5] S. Miyamoto, P. A. Kollman, J. Comput. Chem. 13. (1992). 952.

[6] D. Rozmanov, P. G. Kusalik, Phys. Rev. E. 81. (2010). 056706.

[7] P. Tao, X. Wu, B. R. Brooks, J. Chem. Phys. 137. (2012). 13411108 .

[8] J. P. Ryckaert, G. Ciccotti, H. J. C. Berendsen, J. Comput. Phys. 23. (1977), 327.

[9] B. Hess, H. Bekker, H. J. C. Berendsen, J. G. E. M. Fraaije, J. Comput. Chem. 18. (1997). 1463.

Weak, medium and strong hydrogen bonds revealed by MW spectroscopyWeixing Li1, Iciar Uriarte2, Qian Gou3, Emilio J. Cocinero2, Brooks H. Pate4, Luca

Evangelisti1, Sonia Melandri1, Walther Caminati11 University of Bologna, Bologna, 40126, Italy.

2 Universidad del País Vasco (UPV-EHU), Bilbao, 48940, Spain.3 Chongqing University, Chongqing, 401331, China.

4 University of Virginia, Charlottesville, 400319, [email protected]; [email protected]; [email protected]

1) Oligomers of DFM-water linked by different hydrogen bonds (HB). Guided by theoreticalprediction, the spectra of the hetero-trimers and tetramer of difluoromethane with water have been assignedby Chirped-pulse MW spectrometer. The structures of the oligomers are as shown below.

Besides the normal species we also measured the rotational transitions of the clusters with single, double,triple, and fully deuterated water molecules, respectively.

2) The structure performances of 3,5-Heptandione from isolated to hydrated forms. 3,5-Heptandione possesses many tautomers. Two energetically preferred ones have been unambiguouslyassigned with FTMW spectroscopy. However, its structure has been changed by H2O present in theenvironment, as shown in the figure below. The rotational spectra scans have been extended to theassignment of partial 13C, deuterated, and 18O species.

3) Pure rotational spectrum of the “non-polar” dimer of formic acid. The formic acid dimer is aprototype system to study the strong hydrogen bond formed by carboxyl groups. In principle, it isimpossible to investigate this system using microwave spectroscopy since it has no dipole moment.However for DCOOH-HCOOH, due to a little difference of the vibrations between bonds C-D and C-H, atiny dipole moment is created. This has offered us an opportunity to study this system with FTMW,although very high excitation power is needed (20 Watts). From the fit of the spectra, structuralinformation can be obtained as well as the binding energy, determined to be ~57 kJ/mol. More interesting,the barrier for the double-proton transfer can be determined by the tunneling splitting.

54 55

Poster Poster


Computational study of the DPAP molecular rotor in various environments.Marina Macchiagodena,1 Gianluca Del Frate,1 Giuseppe Brancato,1 Balasubramanian

Chandramouli,1,2 Giordano Mancini1 and Vincenzo Barone11 Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy.

2 Compunet, Istituto Italiano di Tecnologia (IIT), Via Morego 30, 16163 Genova, [email protected]

Fluorescent molecular rotors (FMRs) belong to an important class of environment-sensitive dyes capable to act as nanoprobes to measure the viscosity and polarity of their microenvironment, finding applications in various research fields. Here, we present a multistep protocol for the computational study of a recently proposed FMR, namely 4-(diphenylamino)phthalonitrile (DPAP)[1] which involves the development of a reliable ground state molecular model of the rotor based on quantum-mechanical (QM) calculations, extensive atomistic simulations in different environments and a posteriori spectroscopic calculations of the optical absorption spectra. Special attention has been given to force field parameterization since an accurate model is crucial for the reliability of the simulation results[2]. The new force field has been used to perform molecular dynamics simulations of DPAP in six different environments (acetonitrile, tetrahydrofuran, o-xylene, cyclohexane, lipid bilayer and polymeric matrix) since experimental data on these media have been already published [1]. The chosen solvents cover a broad spectrum of complex molecular embeddings, ranging from apolar/hydrophobic to polar/high-permittivity solvents and from low-density to highly viscous environments, including also a non-homogeneous and anisotropic system. Subtle effects of the molecular interactions with the solvent, the structural fluctuations of the rotor and its rotational dynamics have been analyzed. Results have been correlated with a previous experimental work and provide further insights on the environment-specific properties of the dye[3]. Finally, optical absorption spectra are computed and successfully compared with experiments.

Figure 1 Molecular structure of DPAP molecular rotor.

References [1] M. Koenig et al., Chem. Sci., 4, (2013), 2502.

[2] D. C. Rapaport, The art of molecular dynamics simulation, edited by Cambridge university Press, 2007.

[3] M. Macchiagodena et al., Phys. Chem. Chem. Phys., (2017) doi :10.1039/C7CP04688J.

Development and implementation of new computational methods for the

calculation of accurate equilibrium molecular structures

Marco Mendolicchio, Nicola Tasinato and Vincenzo Barone

Scuola Normale Superiore, Pisa, I-56126, [email protected]

The knowledge of the equilibrium structures of isolated molecular systems of chemical and biological

interest is of fundamental relevance to gain a thorough understanding of many chemical-physicalprocesses, in the framework of the so-called structure-property relationship. Moreover, accurate

equilibrium geometries represent invaluable benchmarks for testing different computational methodsrooted into quantum or classical mechanics. Nowadays, the amount of experimental data is ever increasing,

but these are often influenced by vibrational and/or environmental effects. The molecular structuresobtained through isotopic substitution are vibrationally averaged properties, but vibrational effects are

usually not explicitly considered during the inversion of the spectroscopic data, making the resultingstructures dependent on the isotopic species investigated. In order to overcome these issues, the

determination of the equilibrium structure, defined as the geometry related to the minimum of the Born-Oppenheimer (B-O) potential energy surface (PES), has shown to be the most appealing alternative. This

structure is more challenging to be inferred from the experimental point of view, yet its determinationallows the inclusion of vibrational effects and, within the B-O approximation, it is independent from

isotopic substitutions. Furthermore, they can be directly compared with theoretical results. In this work wepresent the new program MSR (Molecular Structure Refinement), specifically designed for computing

equilibrium structures by means of the semi-experimental approach [1,2]. The program has been equippedwith a flexible choice of the optimization algorithm together with an appropriate treatment of geometrical

constraints and an extended error analysis [3,4]. Particular attention has been devoted to the protocol fordefining automatically the minimum set of non-redundant internal coordinates employable in the fit. The

standard methodology, i.e. the use of the Z-matrix, has proven to be often disadvantageous when complextopologies are investigated, and it is strongly user-dependent. In order to overcome the issues connected

with these internal coordinates, a different procedure has been devised, based on the extraction of all A 1

coordinates from a set of symmetry internal coordinates. This approach, which is particularly useful when

symmetric molecules are considered, is completely automatic and it does not require any intervention fromthe user. The MSR program has been also equipped with the possibility of including predicate observations

[5] in the fit. This approach allows augmenting the set of input data (e.g. rotational constants) throughestimates of structural parameters. In addition to the wide range of computational features, the user-

friendliness of MSR is guaranteed by an intuitive graphical interface from which it can be completelycontrolled and where results are displayed at the end of the structural refinement.

In this contribution, the underlying theory and the structure of our implementation are presented in somedetail. The reliability of the code developed during this work is demonstrated by applications of A1

coordinates and predicate observations to the determination of the equilibrium structure of small- andmedium-size organic molecules.

References

[1] P. Pulay, W. Meyer and J. Boggs, J. Chem. Phys. 68. (1978). 5077.

[2] J. Demaison, Mol. Phys. 105. (2007). 3109.

[3] M. Mendolicchio, E. Penocchio, D. Licari, N. Tasinato, V. Barone, J. Chem. Theory Comput. 13. (2017). 3060.

[4] E. Penocchio, M. Mendolicchio, N. Tasinato, V. Barone, Can. J. Chem. 94. (2016). 12.

[5] L. Bartell, D. Romanesko, T. Wong, G. Sims, L. Sutton, Chemical Society Specialist Periodical Report No. 20:

Molecular Structure by Diffraction Methods. 3. (1975). 72.

56 57

Poster Poster


Structural Properties of Imidazole in Aqueous Solution Marco Pagliai1, Giada Funghi1, Piero Procacci1, Gianni Cardini1

1Dipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, via della Lastruccia 3, Sesto Fiorentino (FI), 50019, Italy.

[email protected]

Imidazole is an aromatic heterocycle with a 5-membered ring. The imidazole ring occurs, as molecule or building block, in systems with important chemical, biological, pharmacological and technological applications [1,2]. In water, at physiological pH, imidazole is present both as neutral and protonated species and interacts with this solvent forming hydrogen bonds [2]. To characterize the structural and dynamic properties of imidazole in water, ab initio molecular dynamics simulations have been performed with the Car-Parrinello method (CPMD) [3]. During these simulations, the potential has been described through the BLYP exchange and correlation functional, whereas the van der Waals interactions have been properly considered with the Grimme method [4].

Since CPMD simulations provide a description of the hydrogen bond interactions in agreement with experimental findings [2], selected results have been adopted to validate a series of force fields for classical molecular dynamics simulations. The new force fields have been employed to simulate imidazole in aqueous solution at the same concentration adopted in neutron scattering experiments [2], to verify the transferability of the model and to obtain useful insights into the imidazole-water and imidazole-imidazole interactions.

References [1] M. S. Shaik, S. Y. Liem, Y. Yuan and P. L. A. Popelier, Phys. Chem. Chem. Phys. 12 (2010) 15040.

[2] E. Duboué-Dijon, P. E. Mason, H. E. Fischer and P. Jungwirth, J. Chem. Phys. 146 (2017) 185102.

[3] R. Car and M. Parrinello, Phys. Rev. Lett. 55 (1985) 2471.

[4] S. Grimme, J. Comput. Chem. 27 (2006) 1787.

Vibrational fingerprints of a promising mimic of the oxygen evolving complexFulvio Perrella1, Umberto Raucci1 and Nadia Rega1,2

1 Department of Chemical Sciences, University Federico II of Napoli, Napoli, 80126, Italy.2 Italian Institute of Technology, IIT@CRIB Center for Advanced Biomaterials for Healthcare,

Napoli, 80126, [email protected]

FTIR spectroscopy has been widely applied to the mechanistic characterization of both the Photosystem II (PSII) oxygen evolving complex (OEC) and the Mn-based water oxidations catalysts (WOCs) employed in artificial photosynthetic devices. In particular, the low-frequency (< 1000 cm-1) region is able to provide direct electronic and structural information about WOCs Mn clusters, because it includes many Mn-ligand and Mn-substrate bands which are sensitive to cluster geometry and to the oxidation state of Mn metal centers. [1,2]

The spectroscopic characterization of the oxidized Sn intermediates (n = 2, 3, 4) of natural and artificial WOCs has been proved quite challenging so far, due to the difficulty in obtaining and stabilising such states. Moreover, the assignment of the IR bands often turned out to be not simple. Therefore, a theoretical approach based on the simulation of IR spectra can be useful to support bands assignments and to validate the structures proposed for the Sn intermediates. In this work we have simulated the low-frequency IR spectrum of a synthetic calcium-tetramanganese [CaMn4O4(t-BuCOO)8(t-BuCOOH)2(py)] complex (t-Bu: tert-butyl, py: pyridine) developed by Zhang and co-workers, characterized by a cubane-like [CaMn4O4]cluster. [3] Beside the striking structural similarity with the native PSII OEC, also the main electronic features of the OEC reactivity appear to be well reproduced by this system, as shown by previous theoretical studies. [4]

A good reproduction of the experimental IR spectrum has been achieved, allowing a straightforward assignment of the observed low-frequency IR bands. In particular, in the 400-750 cm-1 spectral region, as expected, [CaMn4O4] cluster vibrational modes have been observed, together with t-BuCOO- and py bending modes.

The evolution of [CaMn4O4] cluster modes along the catalytic cycle has been then evaluated. IR spectra have been computed for every Sn intermediate (n = -1, 0, 1, 2, 3) in its high-spin state. The comparison of calculated spectra has shown that the position and intensity of most low-frequency IR bands are sensible to the oxidation state of the Mn metal centers. Moreover, IR bands active only for specific Sn states and so having a potential diagnostic relevance have been identified. The insights given by our theoretical approach suggest a structural flexibility of [CaMn4O4] cluster along the OEC catalytic cycle and provide spectroscopic fingerprints of the different Sn intermediates, which can support the interpretation of experimental spectra.

References[1] H.-A. Chu, W. Hillier, N. A. Law, G. T. Babcock, BBA-Bioenergetics 1503 (2001) 69.

[2] R. J. Debus, BBA-Bioenergetics 1847 (2015) 19.

[3] C. Zhang, C. Chen, H. Dong, J.-R. Shen, H. Dau, J. Zhao, Science 348 (2015) 690.

[4] U. Raucci, I. Ciofini, C. Adamo, N. Rega, J. Phys. Chem. Lett. 7 (2016) 5015.

Participants Participants


Carlo Adamo Chimie ParisTech FRANCE

Silvia Alessandrini Scuola Normale Superiore ITALY

Liudmil Antonov Bulgarian Academy of Sciences BULGARIA

Alberto Baiardi Scuola Normale Superiore ITALY

Alice Balbi Scuola Normale Superiore ITALY

Shiladitya Banerjee Scuola Normale Superiore ITALY

Vincenzo Barone Scuola Normale Superiore ITALY

Debora Berti Università degli Studi di Firenze ITALY

Malgorzata Biczysko Shanghai University CHINA

Akash Deep Biswas Scuola Normale Superiore ITALY

Julien Bloino ICCOM-CNR U.O.S. Pisa ITALY

Giulio Bosi Università di Bologna ITALY

Rahma Boussessi Scuola Normale Superiore ITALY

Walther Caminati Università di Bologna ITALY

Chiara Cappelli Scuola Normale Superiore ITALY

Gianni Cardini Università degli Studi di Firenze ITALY

Giulio Cerullo Politecnico di Milano ITALY

Balasubramanian Chandramouli Istituto Italiano di Tecnologia ITALY

James Cheeseman Gaussian, Inc. USA

Riccardo Chelli Università degli Studi di Firenze ITALY

Maria Gabriella Chiariello Università di Napoli Federico II ITALY

Francesco Ciardelli SPIN-PETsrl: UNIPISA ITALY

Salvatore Coluccia Università di Torino ITALY

Federico Coppola Università di Napoli Federico II ITALY

María Pilar de Lara-Castells Consejo Superior de Investigaciones Científicas SPAIN

Silvana De Lillo Università degli Studi di Perugia ITALY

Gianluca Del Frate Scuola Normale Superiore ITALY

Sara Del Galdo Scuola Normale Superiore ITALY

Andreas Dreuw University of Heidelberg GERMANY

Franco Egidi Scuola Normale Superiore ITALY

Luca Evangelisti Università di Bologna ITALY

Emma Fenude ICB-CNR Sassari ITALY

Mariagrazia Fortino Università di Modena e Reggio Emilia ITALY

Alessandro Fortunelli ICCOM-CNR U.O.S. Pisa ITALY

Jacopo Fregoni Università degli Studi di Modena e Reggio Emilia ITALY

Michael Frisch Gaussian, Inc. USA

Marco Fusè Scuola Normale Superiore ITALY

Giovanni Granucci Università di Pisa ITALY

Henrik Koch NTNU NORWAY

Weixing Li Università di Bologna ITALY

Daniele Licari Scuola Normale Superiore ITALY

Filippo Lipparini Università di Pisa ITALY

Jacopo Lupi Scuola Normale Superiore ITALY

Marina Macchiagodena Scuola Normale Superiore ITALY

Giordano Mancini Scuola Normale Superiore ITALY

Tiziana Marino Università della Calabria ITALY

Sonia Melandri Università di Bologna ITALY

Alessio Melli Università di Bologna ITALY

Marco Mendolicchio Scuola Normale Superiore ITALY

Benedetta Mennucci Università di Pisa ITALY

Luca Muccioli Università di Bologna ITALY

Marco Pagliai Università degli Studi di Firenze ITALY

Lorenzo Paoloni Scuola Normale Superiore ITALY

Alfonso Pedone Università di Modena e Reggio Emilia ITALY

Fulvio Perrella Università di Napoli Federico II ITALY

Francesco Poggialini Scuola Normale Superiore ITALY

Andrea Pucci Università di Pisa ITALY

Alessandra Puglisi Scuola Normale Superiore ITALY

Cristina Puzzarini Università di Bologna ITALY

Maria J. Ramos Universidade do Porto PORTUGAL

Sergio Rampino Scuola Normale Superiore ITALY

Umberto Raucci Università di Napoli Federico II ITALY

Nadia Rega Università di Napoli Federico II ITALY

Antonio Rizzo CNR-IPCF ITALY

Walter Rocchia Istituto Italiano di Tecnologia ITALY

Nino Russo Università della Calabria ITALY

Kenneth Ruud University of Tromsø NORWAY

Andrea Salvadori Scuola Normale Superiore ITALY

Monica Sanna Scuola Normale Superiore ITALY

Fabrizio Santoro ICCOM-CNR U.O.S. Pisa ITALY

Dimitrios Skouteris Scuola Normale Superiore ITALY

Lorenzo Spada Scuola Normale Superiore ITALY

Mauro Stener Università di Trieste ITALY

Nicola Tasinato Scuola Normale Superiore ITALY

Sandra Mónica Vieira Pinto Scuola Normale Superiore ITALY

Qin Yang Scuola Normale Superiore ITALY

http://smart.sns.it/erc2017/

Documents

ERC AdG Barone DREAMS 2 DECEMBER 2017 FINAL MEETINGsmart.sns.it/erc2017/20171129-1202 ERC-DREAMS Final OPUSCOLO WEB.pdf · 2 DECEMBER 2017 FINAL MEETING Elaborazione a cura del Servizio