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  1. Article ; 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  Volume 42, Issue 17, Page(s) 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.
    Language English
    Publishing date 2021-05-12
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1479181-X
    ISSN 1096-987X ; 0192-8651
    ISSN (online) 1096-987X
    ISSN 0192-8651
    DOI 10.1002/jcc.26534
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: 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.
    Keywords catalytic activity ; organic chemistry ; stereoselectivity
    Language English
    Dates of publication 2022-0328
    Size p. 5404-5411.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.2c00302
    Database NAL-Catalogue (AGRICOLA)

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  3. Article ; Online: Direct Synthesis of CF

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

    Organic letters

    2021  Volume 23, Issue 14, Page(s) 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
    Language English
    Publishing date 2021-06-30
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1523-7052
    ISSN (online) 1523-7052
    DOI 10.1021/acs.orglett.1c01876
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: One-Pot anti-Michael Regio- and Stereoselective Hydroamination of Activated

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

    The Journal of organic chemistry

    2022  Volume 87, Issue 8, Page(s) 5404–5411

    Abstract: ... ...

    Abstract N
    MeSH term(s) Amines ; Catalysis ; Copper ; Stereoisomerism
    Chemical Substances Amines ; Copper (789U1901C5)
    Language English
    Publishing date 2022-03-28
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.2c00302
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Modeling the spectral properties of poly(x-phenylenediamine) conducting polymers using a combined TD-DFT and electrostatic embedding approach.

    Luise, Davide / D'Alterio, Massimo Christian / Talarico, Giovanni / Ciofini, Ilaria / Labat, Frédéric

    Journal of computational chemistry

    2022  Volume 43, Issue 30, Page(s) 2001–2008

    Abstract: The absorption spectra of polymers derived from ortho, meta and para phenylenediamines (o-PDA, m-PDA and p-PDA) have been simulated combining periodic density functional theory (DFT) calculations with time-dependent DFT simulations. These latter have ... ...

    Abstract The absorption spectra of polymers derived from ortho, meta and para phenylenediamines (o-PDA, m-PDA and p-PDA) have been simulated combining periodic density functional theory (DFT) calculations with time-dependent DFT simulations. These latter have been carried out on finite clusters embedded in a set of point charges devised to exactly reproduce the electrostatic potential of the periodic chains. The results are compared with those obtained for solvated o-PDA, m-PDA and p-PDA oligomers of increasing sizes extracted from the periodic structures. The electronic transitions involved have been investigated by a qualitative analysis based on isodensity maps completed by a quantitative analysis based on the density-based index (D
    Language English
    Publishing date 2022-06-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1479181-X
    ISSN 1096-987X ; 0192-8651
    ISSN (online) 1096-987X
    ISSN 0192-8651
    DOI 10.1002/jcc.26955
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Copper-Catalyzed Synthesis of Terminal vs. Fluorine-Substituted N-Allenamides via Addition of Diazo Compounds to Terminal Ynamides.

    Zheng, Yongxiang / Moegle, Baptiste / Ghosh, Santanu / Perfetto, Anna / Luise, Davide / Ciofini, Ilaria / Miesch, Laurence

    Chemistry (Weinheim an der Bergstrasse, Germany)

    2021  Volume 28, Issue 1, Page(s) e202103598

    Abstract: A copper-mediated coupling reaction between ynamides and diazo-compounds to produce N-allenamides is reported for the first time. This method enables facile and rapid access to terminal N-allenamides by using commercially available TMS-diazomethane with ... ...

    Abstract A copper-mediated coupling reaction between ynamides and diazo-compounds to produce N-allenamides is reported for the first time. This method enables facile and rapid access to terminal N-allenamides by using commercially available TMS-diazomethane with wide functional group compatibility on the nitrogen. Furthermore, the ubiquity of molecules containing a fluorine moiety in medicine, in agricultural, and material science requires the continuous search of new building blocks, including this unique surrogate. The CuI/diazo protocol was successfully applied to the synthesis of fluorine-substituted N-allenamides. DFT calculations provided insights in the mechanism involved.
    MeSH term(s) Azo Compounds ; Catalysis ; Copper ; Fluorine
    Chemical Substances Azo Compounds ; Fluorine (284SYP0193) ; Copper (789U1901C5)
    Language English
    Publishing date 2021-12-09
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1478547-X
    ISSN 1521-3765 ; 0947-6539
    ISSN (online) 1521-3765
    ISSN 0947-6539
    DOI 10.1002/chem.202103598
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: In-Depth Analysis of the Nonuniform Chain Microstructure of Multiblock Copolymers from Chain-Shuttling Polymerization

    Urciuoli, Gaia / Vittoria, Antonio / Talarico, Giovanni / Luise, Davide / De Rosa, Claudio / Busico, Vincenzo / Cipullo, Roberta / Ruiz de Ballesteros, Odda / Auriemma, Finizia

    Macromolecules. 2021 Nov. 18, v. 54, no. 23

    2021  

    Abstract: The nonuniform molecular architecture of ethylene/1-octene multiblock copolymers (O-MBCs) synthesized by the chain shuttling technology is investigated. The samples consist of chains characterized by alternating hard (crystalline) and soft (amorphous) ... ...

    Abstract The nonuniform molecular architecture of ethylene/1-octene multiblock copolymers (O-MBCs) synthesized by the chain shuttling technology is investigated. The samples consist of chains characterized by alternating hard (crystalline) and soft (amorphous) blocks, corresponding to random ethylene/1-alkene copolymers with a low and high comonomer content, respectively. The chains are nonuniform as the distribution in the length and number of blocks per chain are statistical and vary from chain to chain. A clear-cut investigation of the inter- and intrachain constitutional heterogeneity of O-MBCs is performed by carrying out, at first, a sequential and exhaustive solvent fractionation procedure in boiling solvents, that is, diethyl ether, n-hexane, and cyclohexane. Successively, the unfractionated samples and the corresponding fractions are subjected to analytical crystallization elution fractionation (aCEF), solution ¹³C NMR, differential scanning calorimetry, and wide- and small-angle X-ray scattering (SAXS) analyses. Four fractions of increasing average ethylene content, hard block content, and degree of crystallinity are obtained, that is, a fraction soluble in diethyl ether (sEE), a fraction insoluble in diethyl ether/soluble in n-hexane (iEE-sC6), a fraction insoluble in n-hexane/soluble in cyclohexane (iC6-sCC6), and a fraction insoluble in cyclohexane (iCC6). The results of aCEF and ¹³C NMR analysis highlight that the multiblock chain microstructure of the O-MBCs corresponds to a statistical distribution of the length of hard and soft blocks that occurs not only at an interchain level but also at an intrachain level. SAXS measurements essentially confirm the results of the microstructural analysis and allow achieving a quantitative description of the constitutional heterogeneity affecting O-MBCs at the intramolecular level. In particular, it is shown that for the inferior fractions (sEE and iEE-sC6), the chains include hard blocks of low molecular mass (<1 kDa) covalently linked to short and long soft blocks in the iEE-sC6 and sEE fractions, respectively. For the superior fractions (iC6-sCC6 and iCC6), instead, it is shown that the chains include hard blocks of significantly different molecular masses that experience molecular fractionation by the effect of crystallization, the molecular mass of the hard MH and soft MS blocks in the HS units being comprised in between 2 and 16 and 6 and 44 kDa, respectively. These characteristics explain quite well the fractionation behavior of the O-MBCs, highlighting that the solubility in a given solvent does not depend exclusively on the length and the content of hard blocks but is critically dependent also on the length and content of soft blocks.
    Keywords chemical bonding ; clearcutting ; composite polymers ; crystal structure ; crystallization ; cyclohexanes ; ethyl ether ; ethylene ; fractionation ; hexane ; microstructure ; molecular weight ; polymerization ; small-angle X-ray scattering ; solubility ; solvents
    Language English
    Dates of publication 2021-1118
    Size p. 10891-10902.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 1491942-4
    ISSN 1520-5835 ; 0024-9297
    ISSN (online) 1520-5835
    ISSN 0024-9297
    DOI 10.1021/acs.macromol.1c01824
    Database NAL-Catalogue (AGRICOLA)

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