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Web of Science [V.5.28] - WOS Export Transfer Service Web of Science [v.5.28] - WOS Export Transfer Service http://ets.webofknowledge.com/ETS/ets.do?SID=E3coQ5BgUvSvQ9dgbg6&product=... Close Web of Science Print Page 1 (Records 1 -- 50) [ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 ] Record 1 of 491 Title: Raman antenna effect from exciton-phonon coupling in organic semiconducting nanobelts Author(s): Wang, M (Wang, Mao); Gong, Y (Gong, Yi); Alzina, F (Alzina, Francesc); Svoboda, O (Svoboda, Ondrej); Ballesteros, B (Ballesteros, Belen); Torres, CMS (Sotomayor Torres, Clivia M.); Xiao, SB (Xiao, Senbo); Zhang, ZL (Zhang, Zhiliang); He, JY (He, Jianying) Source: NANOSCALE Volume: 9 Issue: 48 Pages: 19328-19336 DOI: 10.1039/c7nr07212k Published: DEC 28 2017 Abstract: The highly anisotropic interactions in organic semiconductors together with the soft character of organic materials lead to strong coupling between nuclear vibrations and exciton dynamics, which potentially results in anomalous electrical, optical and optoelectrical properties. Here, we report on the Raman antenna effect from organic semiconducting nanobelts 6,13-dichloropentacene (DCP), resulting from the coupling of molecular excitons and intramolecular phonons. The highly ordered crystalline structure in DCP nanobelts enables the precise polarization-resolved spectroscopic measurement. The angle-dependent Raman spectroscopy under resonant excitation shows that all Raman modes from the skeletal vibrations of DCP molecule act like a nearly perfect dipole antenna I-Raman proportional to cos(4)(theta - 90), with almost zero (maximum) Raman scattering parallel (perpendicular) to the nanobelt's long-axis. The Raman antenna effect in DCP nanobelt is originated from the coupling between molecular skeletal vibrations and intramolecular exciton and the confinement of intermolecular excitons. It dramatically enhances the Raman polarization ratio (rho = I-parallel to/I-perpendicular to > 25) and amplifies the anisotropy of the angle-dependent Raman scattering (kappa(Raman) = I-max/I-min > 12) of DCP nanobelts. These findings have crucial implications for fundamental understanding on the exciton-phonon coupling and its effects on the optical properties of organic semiconductors. Accession Number: WOS:000418098000039 Author Identifiers: Author ResearcherID Number ORCID Number Ballesteros, Belen B-1167-2010 0000-0002-1958-8911 Alzina, Francesc C-5468-2008 0000-0002-7082-0624 He, Jianying C-8747-2009 0000-0001-8485-7893 Sotomayor Torres, Clivia E-8418-2010 0000-0001-9986-2716 0000-0002-9557-3455 ISSN: 2040-3364 eISSN: 2040-3372 Record 2 of 491 Title: Spin-orbit driven phenomena in the isoelectronic L1(0)-Fe(Pd,Pt) alloys from first principles Author(s): Kudrnovsky, J (Kudrnovsky, J.); Drchal, V (Drchal, V.); Turek, I (Turek, I.) Source: PHYSICAL REVIEW B Volume: 96 Issue: 21 Article Number: 214437 DOI: 10.1103/PhysRevB.96.214437 Published: DEC 26 2017 Abstract: The anomalous Hall effect (AHE) and the Gilbert damping (GD) are studied theoretically for the partially ordered L1(0)-Fe(Pd,Pt) alloys. The varying alloy order and the spin-orbit coupling, which are due to the change in the Pd/Pt composition, allow for a chemical tuning of both phenomena which play an important role in the spintronic applications. The impact of the antisite disorder on the residual resistivity, AHE, and GD is studied from first principles using recently developed methods employing the Kubo-Bastin approach and the nonlocal torque operator method. The most interesting result is a different behavior of samples with low and high chemical orders. Good agreement between calculated and measured concentration trends is obtained for all quantities studied, while the absolute GD values are underestimated. Accession Number: WOS:000418653000009 Author Identifiers: Author ResearcherID Number ORCID Number Turek, Ilja G-5553-2014 0000-0002-0604-6590 ISSN: 2469-9950 eISSN: 2469-9969 Record 3 of 491 Title: The benchmark of P-31 NMR parameters in phosphate: a case study on structurally constrained and flexible phosphate Author(s): Fukal, J (Fukal, Jiri); Pav, O (Pav, Ondrej); Budesinsky, M (Budesinsky, Milos); Sebera, J (Sebera, Jakub); Sychrovsky, V (Sychrovsky, Vladimir) Source: PHYSICAL CHEMISTRY CHEMICAL PHYSICS Volume: 19 Issue: 47 Pages: 31830-31841 DOI: 10.1039/c7cp06969c Published: DEC 21 2017 Abstract: A benchmark for structural interpretation of the P-31 NMR shift and the (2)J(P),(C) NMR spin-spin coupling in the phosphate group was obtained by means of theoretical calculations and NMR measurements in diethylphosphate (DEP) and 5,5-dimethyl-2-hydroxy-1,3,2-dioxaphosphinane 2-oxide (cDEP). The NMR parameters were calculated employing the B3LYP, BP86, BPW91, M06-2X, PBE0, KT2, KT3, MP2, and HF methods, and the 6-31+G(d), Iglo-n (n = II, III), cc-pVnZ (n = D, T, Q, 5), aug-cc-pVnZ (n = D, T and Q), and pcS-n and pcJ-n (n = 1, 2, 3, 4) bases, including the solvent effects described with explicit water molecules and/or the implicit Polarizable Continuum Model (PCM). The effect of molecular dynamics (MD) on NMR parameters was MD-calculated using the GAFF force field inclusive of explicit hydration with TIP3P water molecules. Both the optimal geometries and the dynamic behaviors of the DEP and cDEP phosphates differed notably, which allowed a reliable theoretical benchmark of the P-31 NMR parameters for highly flexible and structurally constrained phosphate in a one-to-one relationship with the corresponding experiment. The calculated P-31 NMR shifts were referenced employing three different NMR reference schemes to highlight the effect of the P-31 NMR reference on the accuracy of the calculated P-31 NMR shift. The relative Dd(P-31) NMR shift calculated employing the MD/B3LYP/Iglo-III/PCM method differed from the experiment by 0.16 ppm while the NMR shifts referenced to H3PO4 and/or PH3 deviated from the experiment notably more, which illustrated the superior applicability of the relative NMR reference scheme. The (2)J(P,C) coupling in DEP and cDEP calculated employing theMD/B3LYP/Iglo- III(DSO,PSO,SD)/cc-PV5Z(FC)/PCM method inclusive of correction due to explicit hydration differed from the experiment by 0.32 Hz and 0.15 Hz, respectively. The NMR calculations demonstrated that reliable structural interpretation of the P-31 NMR parameters in phosphate must involve both the structural and the dynamical components. Accession Number: WOS:000417295800034 PubMed ID: 29171602 Author Identifiers: Author ResearcherID Number ORCID Number Sebera, Jakub B-6112-2013 0000-0001-5671-5206 ISSN: 1463-9076 eISSN: 1463-9084 Record 4 of 491 Title: Chiral ethylene-bridged flavinium salts: the stereoselectivity of flavin-10a-hydroperoxide formation and the effect of substitution on the photochemical properties Author(s): Zurek, J (Zurek, Jiri); Svobodova, E (Svobodova, Eva); Sturala, J (Sturala, Jiri); Dvorakova, H (Dvorakova, Hana); Svoboda, J (Svoboda, Jiri); Cibulka, R (Cibulka, Radek) Source: TETRAHEDRON-ASYMMETRY Volume: 28 Issue: 12 Pages: 1780-1791 DOI: 10.1016/j.tetasy.2017.10.029 Published: DEC 15 2017 Abstract: A series of chiral non-racemic N-1,N-10-ethylene bridged flavinium salts 4 was prepared using enantiomerically pure 2-substituted 2-aminoethanols (R = isopropyl, phenyl, benzyl, 4-methoxybenzyl, 4-benzyloxybenzyl) derived from amino acids as the sole source of chirality. The flavinium salts were shown to form 10a-hydroperoxy- and 10a- methoxy-adducts with moderate to high diastereoselectivity depending on the ethylene bridge substituent originating from the starting amino acid. High diastereoselectivities (dr values from 80:20 to >95:5) were observed for flavinium salts bearing benzyl substituents attached to the ethylene bridge. The benzyl group preferred the face-to-face (syn) orientation relative to the flavinium unit; thereby effectively preventing nucleophilic attack from one side. This conformation was found to be the most stable according to the DFT calculations. Consequently, the presence of benzyl groups causes intermolecular fluorescence quenching resulting in a significant decrease in the fluorescence quantum yield from 11% for 4a bearing an isopropyl substituent to 0.3% for 4c containing a benzyl group and to a value lower than 0.1% for the benzyloxybenzyl derivative 4e. (C) 2017 Elsevier Ltd. All rights reserved. Accession Number: WOS:000418988400014 Author Identifiers: 1 z 13 13.04.2018 15:06 Web of Science [v.5.28] - WOS Export Transfer Service http://ets.webofknowledge.com/ETS/ets.do?SID=E3coQ5BgUvSvQ9dgbg6&product=... Author ResearcherID Number ORCID Number Sturala, Jiri 0000-0002-8113-0709 ISSN: 0957-4166 Record 5 of 491 Title: Unexpected Crystallization Patterns of Zinc Boron Imidazolate Framework ZBIF-1: NMR Crystallography of Integrated Metal-Organic Frameworks Author(s): Kobera, L (Kobera, Libor); Rohlicek, J (Rohlicek, Jan); Czernek, J (Czernek, Jiri); Abbrent, S (Abbrent, Sabina); Streckova, M (Streckova, Magdalena); Sopcak, T (Sopcak, Tibor); Brus, J (Brus, Jiri) Source: CHEMPHYSCHEM Volume: 18 Issue: 24 Pages: 3576-3582 DOI: 10.1002/cphc.201701063 Published: DEC 15 2017 Abstract: Framework materials, that is, metal-organic frameworks (MOFs) and inorganic frameworks (zeolites), are porous systems with regular structures that provide valuable properties suitable for sorption, catalysis, molecular sieving, and so on. Herein, an efficient, experimental/computational strategy is presented that allows detailed characterization of a polycrystalline MOF system, namely, zinc boron imidazolate framework ZBIF-1, with two integrated unit cells on the atomic-resolution
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