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  1. Artikel ; Online: Monitoring Density Redistribution at the Excited State in a Dual Emitting Molecule: An Analysis Based on Real-Time Density Functional Theory and Density Descriptors.

    Korsaye, Feven-Alemu / Perrella, Fulvio / Petrone, Alessio / Adamo, Carlo / Rega, Nadia / Ciofini, Ilaria

    The journal of physical chemistry. A

    2024  

    Abstract: In this work, we computed and analyzed, by means of density-based descriptors, the real-time evolution of both the locally excited (LE) and charge-transfer (CT) excited states for the planar and twisted conformations of the DMABN (4-( ...

    Abstract In this work, we computed and analyzed, by means of density-based descriptors, the real-time evolution of both the locally excited (LE) and charge-transfer (CT) excited states for the planar and twisted conformations of the DMABN (4-(
    Sprache Englisch
    Erscheinungsdatum 2024-05-17
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ISSN 1520-5215
    ISSN (online) 1520-5215
    DOI 10.1021/acs.jpca.4c00934
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  2. Artikel: On the Interplay between Molecular Packing and Optical Response in Thin Films for Organic Photovoltaics

    Turelli, Michele / Lattanzi, Gianluca / Ciofini, Ilaria / Adamo, Carlo

    Journal of physical chemistry. 2021 July 15, v. 125, no. 29

    2021  

    Abstract: Limited control over the complex morphology exhibited by organic materials in the solid phase constitutes one of the greatest challenges to power conversion enhancement in the field of organic photovoltaics. Often, this problem is made worse by the ... ...

    Abstract Limited control over the complex morphology exhibited by organic materials in the solid phase constitutes one of the greatest challenges to power conversion enhancement in the field of organic photovoltaics. Often, this problem is made worse by the molecular architecture of the building blocks engineered with complex structures that make the mechanisms of self-organization less straightforward and less efficient. Here, we present the computational study of a small-molecule donor with a simple architecture whose absorption spectrum in thin film experiences a dramatic change upon thermal treatment. In our present study, this change is rationalized in terms of reorganization of the molecular packing within the film. This reorganization is described in its microscopic details: the results of our simulations provide a plausible picture of the macroscopic thin-film morphology, thus offering valuable hints on how to improve the control of morphology in molecular solids.
    Schlagwörter films (materials) ; heat treatment ; physical chemistry ; solar energy ; spectral analysis
    Sprache Englisch
    Erscheinungsverlauf 2021-0715
    Umfang p. 16304-16315.
    Erscheinungsort American Chemical Society
    Dokumenttyp Artikel
    ISSN 1932-7455
    DOI 10.1021/acs.jpcc.1c03998
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  3. Artikel ; Online: Free Energy Profiles of Proton Transfer Reactions: Density Functional Benchmark from Biased Ab Initio Dynamics.

    Brémond, Éric / Savarese, Marika / Rega, Nadia / Ciofini, Ilaria / Adamo, Carlo

    Journal of chemical theory and computation

    2022  Band 18, Heft 3, Seite(n) 1501–1511

    Abstract: By coupling an enhanced sampling algorithm with an orbital-localized variant of Car-Parrinello molecular dynamics, the so-called atomic centered density matrix propagation model, we reconstruct the free energy profiles along reaction pathways using ... ...

    Abstract By coupling an enhanced sampling algorithm with an orbital-localized variant of Car-Parrinello molecular dynamics, the so-called atomic centered density matrix propagation model, we reconstruct the free energy profiles along reaction pathways using different density functional approximations (DFAs) ranging from locals to hybrids. In particular, we compare the computed free energy barrier height of proton transfer (PT) reactions to those obtained by a more traditional static approach, based on the intrinsic reaction coordinate (IRC), for two case systems, namely malonaldehyde and formic acid dimer. The obtained results show that both the IRC profiles and the potentials of mean force, derived from biased dynamic trajectories, are very sensitive to the density functional approximation applied. More precisely, we observe that, with the notable exception of M06-L, local density functionals always strongly underestimate the reaction barrier heights. More generally, we find that also the shape of the free energy profile is very sensitive to the density functional choice, thus highlighting the effect, often neglected, that the choice of DFA has also in the case of dynamics simulations.
    Sprache Englisch
    Erscheinungsdatum 2022-02-07
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ISSN 1549-9626
    ISSN (online) 1549-9626
    DOI 10.1021/acs.jctc.1c01002
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  4. Artikel ; Online: Organic compounds for solid state luminescence enhancement/aggregation induced emission: a theoretical perspective.

    Turelli, Michele / Ciofini, Ilaria / Wang, Qinfan / Ottochian, Alistar / Labat, Frédéric / Adamo, Carlo

    Physical chemistry chemical physics : PCCP

    2023  Band 25, Heft 27, Seite(n) 17769–17786

    Abstract: Organic luminophores displaying one or more forms of luminescence enhancement in solid state are extremely promising for the development and performance optimization of functional materials essential to many modern key technologies. Yet, the effort to ... ...

    Abstract Organic luminophores displaying one or more forms of luminescence enhancement in solid state are extremely promising for the development and performance optimization of functional materials essential to many modern key technologies. Yet, the effort to harness their huge potential is riddled with hurdles that ultimately come down to a limited understanding of the interactions that result in the diverse molecular environments responsible for the macroscopic response. In this context, the benefits of a theoretical framework able to provide mechanistic explanations to observations, supported by quantitative predictions of the phenomenon, are rather apparent. In this perspective, we review some of the established facts and recent developments about the current theoretical understanding of solid-state luminescence enhancement (SLE) with an accent on aggregation-induced emission (AIE). A description of the macroscopic phenomenon and the questions it raises is accompanied by a discussion of the approaches and quantum chemistry methods that are more apt to model these molecular systems with the inclusion of an accurate yet efficient simulation of the local environment. A sketch of a general framework, building from the current available knowledge, is then attempted
    Sprache Englisch
    Erscheinungsdatum 2023-07-12
    Erscheinungsland England
    Dokumenttyp Journal Article ; Review
    ZDB-ID 1476244-4
    ISSN 1463-9084 ; 1463-9076
    ISSN (online) 1463-9084
    ISSN 1463-9076
    DOI 10.1039/d3cp02364h
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  5. Artikel ; Online: Following the density evolution using real time density functional theory and density based indexes: Application to model push-pull molecules.

    Korsaye, Feven Alemu / de la Lande, Aurélien / Ciofini, Ilaria

    Journal of computational chemistry

    2022  Band 43, Heft 22, Seite(n) 1464–1473

    Abstract: Considering as test case a family of organic rod like push-pull molecules, we derived and applied density based index enabling the description and diagnostic of the electronic density evolution in real time-time dependent density functional theory (RT- ... ...

    Abstract Considering as test case a family of organic rod like push-pull molecules, we derived and applied density based index enabling the description and diagnostic of the electronic density evolution in real time-time dependent density functional theory (RT-TDDFT) simulations. In particular, both the charge transfer (CT) distance and a diagnostic index, the D
    Mesh-Begriff(e) Density Functional Theory
    Sprache Englisch
    Erscheinungsdatum 2022-06-29
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 1479181-X
    ISSN 1096-987X ; 0192-8651
    ISSN (online) 1096-987X
    ISSN 0192-8651
    DOI 10.1002/jcc.26932
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  6. Artikel ; Online: Concerted versus stepwise proton transfer reactions in the [2, 2'-bipyridyl]-3-3'-diol molecule: A static and dynamic ab-initio investigation.

    Briccolani-Bandini, Lorenzo / Brémond, Eric / Pagliai, Marco / Cardini, Gianni / Ciofini, Ilaria / Adamo, Carlo

    Journal of computational chemistry

    2023  Band 44, Heft 30, Seite(n) 2308–2318

    Abstract: The double proton transfer (PT) reaction has been investigated in the [2,2'-bipyridyl]-3-3'-diol, a complex molecule where the proton movements is coupled to significant rearrangement of the electronic structure. Moreover, the reaction could be concerted, ...

    Abstract The double proton transfer (PT) reaction has been investigated in the [2,2'-bipyridyl]-3-3'-diol, a complex molecule where the proton movements is coupled to significant rearrangement of the electronic structure. Moreover, the reaction could be concerted, that is the two protons are exchanged simultaneously, or stepwise, where the two protons are transferred sequentially. To this end, a static exploration of the potential energy surface (PES) was carried together with the analysis of the free-energy surface (FES), both surfaces being evaluated at density functional theory level and different exchange-correlation functionals. While the concerted mechanism has been clearly discharged, the characteristics of the stepwise PT significantly depends on the chosen functionals, some suggesting a clear stepwise mechanism characterized by a stable reaction intermediates and two transitions states, whereas other approaches propend for a asynchronous PT, with a single TS. These features appear on both PES and FES, albeit some differences appears due to their different nature.
    Sprache Englisch
    Erscheinungsdatum 2023-08-16
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 1479181-X
    ISSN 1096-987X ; 0192-8651
    ISSN (online) 1096-987X
    ISSN 0192-8651
    DOI 10.1002/jcc.27198
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  7. Artikel ; Online: Modeling UV-Vis spectra of low dimensional materials using electrostatic embedding: The case of CdSe.

    Luise, Davide / Wilbraham, Liam / Labat, Frédéric / Ciofini, Ilaria

    Journal of computational chemistry

    2021  Band 42, Heft 17, Seite(n) 1212–1224

    Abstract: We present a generalization of a self-consistent electrostatic embedding approach (SC-Ewald) devised to investigate the photophysical properties of 3D periodic materials, to systems in one- or two-dimensional (2D) reduced periodicity. In this approach, ... ...

    Abstract We present a generalization of a self-consistent electrostatic embedding approach (SC-Ewald) devised to investigate the photophysical properties of 3D periodic materials, to systems in one- or two-dimensional (2D) reduced periodicity. In this approach, calculations are carried out on a small finite molecular cluster extracted from a periodic model, while the crystalline environment is accounted for by an array of point charges which are fitted to reproduce the exact electrostatic potential (at ground or the excited state) of the infinite periodic system. Periodic density functional theory (DFT) calculations are combined with time dependent DFT calculations to simulate absorption and emission properties of the extended system under investigation. We apply this method to compute the UV-Vis. spectra of bulk and quantum-confined 0D quantum dots and 2D extended nanoplatelets of CdSe, due to their relevance as sensitizers in solar cells technologies. The influence of the size and shape of the finite cluster model chosen in the excited state calculations was also investigated and revealed that, although the long-range electrostatics of the environment are important for the calculation of the UV-Vis, a subtle balance between short- and long-range effects exists. These encouraging results demonstrate that this self-consistent electrostatic embedding approach, when applied in different dimensions, can successfully model the photophysical properties of diverse material classes, making it an attractive low-cost alternative to far more computationally demanding electronic structure methods for excited state calculations.
    Sprache Englisch
    Erscheinungsdatum 2021-05-12
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 1479181-X
    ISSN 1096-987X ; 0192-8651
    ISSN (online) 1096-987X
    ISSN 0192-8651
    DOI 10.1002/jcc.26534
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  8. Artikel: One-Pot anti-Michael Regio- and Stereoselective Hydroamination of Activated N-Allenamides

    Hourtoule, Maxime / Zheng, Yongxiang / Perfetto, Anna / Luise, Davide / Ciofini, Ilaria / Miesch, Laurence

    Journal of organic chemistry. 2022 Mar. 28, v. 87, no. 8

    2022  

    Abstract: N-Allenamides, substituted by an ester at the γ-position, were obtained through addition of terminal ynamides with ethyl diazoacetate under copper catalysis for the first time. Regio- and stereoselective hydroamination of those activated N-allenamides ... ...

    Abstract N-Allenamides, substituted by an ester at the γ-position, were obtained through addition of terminal ynamides with ethyl diazoacetate under copper catalysis for the first time. Regio- and stereoselective hydroamination of those activated N-allenamides provided exclusively E-configured captodative enamimes through a one-pot anti-Michael addition. Numerous ynamides as well as various secondary amines were adapted in this process.
    Schlagwörter catalytic activity ; organic chemistry ; stereoselectivity
    Sprache Englisch
    Erscheinungsverlauf 2022-0328
    Umfang p. 5404-5411.
    Erscheinungsort American Chemical Society
    Dokumenttyp Artikel
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.2c00302
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  9. Artikel ; Online: Electron Spin Densities and Density Functional Approximations: Open-Shell Polycyclic Aromatic Hydrocarbons as Case Study.

    Savarese, Marika / Brémond, Éric / Ciofini, Ilaria / Adamo, Carlo

    Journal of chemical theory and computation

    2020  Band 16, Heft 6, Seite(n) 3567–3577

    Abstract: The way different density functional approximations (DFAs) are able to predict, in open-shell systems, spin density, that is the difference between the densities of electrons with spin α and those of spin β, is investigated. Here, a large panel of ... ...

    Abstract The way different density functional approximations (DFAs) are able to predict, in open-shell systems, spin density, that is the difference between the densities of electrons with spin α and those of spin β, is investigated. Here, a large panel of functionals were tested on a set composed of seven π-radicals expected to amplify DFA errors in modeling electron delocalization and spin polarization effects due to their extended electronic conjugation coupled with their planar structures. Our results show that generally the DFA performances follow a systematic improvement in going from semilocal to hybrid functionals. More problematic is, instead, the case of double hybrid functionals, where the perturbative contribution to correlation damps the positive effect of the presence of a high percent of exact exchange. More interestingly, differences are observed in the spin delocalization and polarization patterns, thus restraining the possibility of applying some of current DFAs to study chemically relevant properties, like molecular magnetism or charge/electron transport.
    Sprache Englisch
    Erscheinungsdatum 2020-05-29
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ISSN 1549-9626
    ISSN (online) 1549-9626
    DOI 10.1021/acs.jctc.0c00059
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  10. Artikel ; Online: Direct Synthesis of CF

    Zheng, Yongxiang / Perfetto, Anna / Luise, Davide / Ciofini, Ilaria / Miesch, Laurence

    Organic letters

    2021  Band 23, Heft 14, Seite(n) 5528–5532

    Abstract: The significance of molecules containing difluoromethyl groups is driven by their potential applications in pharmaceutical and agrochemical science. Methods for the incorporation of lightly fluorinated groups such as ... ...

    Abstract The significance of molecules containing difluoromethyl groups is driven by their potential applications in pharmaceutical and agrochemical science. Methods for the incorporation of lightly fluorinated groups such as CF
    Sprache Englisch
    Erscheinungsdatum 2021-06-30
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1523-7052
    ISSN (online) 1523-7052
    DOI 10.1021/acs.orglett.1c01876
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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