排序方式: 共有86条查询结果,搜索用时 15 毫秒
81.
Yu. V. Lavskaya A. V. Okotrub L. G. Bulusheva E. M. Pazhetnov A. I. Boronin N. I. Denisenko O. V. Boltalina 《Physics of the Solid State》2007,49(6):1195-1200
The structure of the fullerence fluoride C60F24 of the T h symmetry contains two types of chemically different carbon atoms, namely, atoms of isolated double bonds and atoms of CF groups. X-ray photoelectron and x-ray emission spectroscopic studies of C60F24 revealed a difference in the widths of the x-ray bands corresponding to these types of atoms. Nonempirical quantum-chemical calculations performed for C59NF 24 + ions with a hole in the C 1s core level of the fullerence fluoride showed that the difference in the bandwidths may be due to the fact that the vibrational states of the system are different when 1s electrons are removed from chemically nonequivalent atoms. 相似文献
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Popov AA Kareev IE Shustova NB Lebedkin SF Strauss SH Boltalina OV Dunsch L 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(1):107-121
Eight new C70(CF3)n derivatives (n=2, 6, 10, 12) have been synthesized and characterized by UV/Vis and 19F NMR spectroscopy, cyclic voltammetry, and quantum chemical calculations at the DFT level of theory. Nine previously known derivatives of C70(CF3)n with n=2-12 were also studied by cyclic voltammetry (and seven of them by UV/Vis spectroscopy for the first time). Most of the 17 compounds exhibited two or three reversible reductions at scan rates from 20 mV s(-1) up to 5.0 V s(-1). In general, reduction potentials for the 0/- couple are shifted anodically relative to the C70 0/-) couple. However, the 0/- E1/2 values for a given composition are strongly dependent on the addition pattern of the CF3 groups. The data show that the addition pattern is as important, if not more important in some cases, than the number of substituents, n, in determining E1/2 values. An analysis of the DFT-predicted LUMOs indicates that addition patterns that have non-terminal double bonds in pentagons result in derivatives that are strong electron acceptors. 相似文献
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Kuvychko IV Spisak SN Chen YS Popov AA Petrukhina MA Strauss SH Boltalina OV 《Angewandte Chemie (International ed. in English)》2012,51(20):4939-4942
Lots of potential: a trifluoromethylated corannulene, C(5)-C(20)H(5)(CF(3))(5), has been prepared and characterized spectroscopically and by X-ray crystallography. The structure exhibits a highly ordered bowl stacking that is unusual for corannulenes with acyclic substituents. The first reduction of C(5)-C(20)H(5)(CF(3))(5) is anodically shifted by 0.95 V, making it the strongest corannulene-based electron acceptor to date. 相似文献
86.
Vasil'ev YV Khvostenko OG Streletskii AV Boltalina OV Kotsiris SG Drewello T 《The journal of physical chemistry. A》2006,110(18):5967-5972
DCTB [(H(3)C)(3)C-p-Ph-CH=C(CH(3))-trans-CH=C(CN)(2)] has recently advanced to the most promising matrix material for matrix-assisted laser desorption/ionization (MALDI) within material sciences. However, data that would allow the evaluation of the electron-transfer reactivity within a thermochemical framework are sparse. The present study reports the first-time determination of the ionization energy (IE) of DCTB applying photoelectron (PE) spectroscopy. The experimental IE (8.54 +/- 0.05 eV) is in excellent agreement with the theoretical value of 8.47 eV, obtained by AM1 calculations. The same level of theory determines the electron affinity (EA) as 2.31 eV. Model analytes of known thermochemistry (phenanthrene [C(14)H(10)], anthracene [C(14)H(10)] and fluorofullerene [C(60)F(46/48)]) are used to bracket the electron-transfer reactivity within DCTB-MALDI. The formation of molecular ions of these analytes either is expected or is beyond the thermochemical accessibility of the DCTB matrix. 相似文献