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2.
According to the data of UHF/INDO calculations of the model conformations of fluorinated nitrobenzene radical anions, rotation of the nitro group relative to the plane of the benzene ring is accompanied by a pyramidal distortion of the group, which is of pseudo-Jahn–Teller nature. The degree of structural distortions depends on the position of the fluorine atoms in the benzene ring and on the solvent, increasing from DMF to DMF–water mixtures. The values of isotropic hyperfine interaction constants are interpreted in the series of fluorinated nitrobenzene radical anions, and the effects of water content in binary mixtures of solvents are discussed.  相似文献   
3.
Conclusions A method has been proposed for the synthesis of N-(5-tetrazolyl)amidines from 5-amino-tetrazole, nitriles, and organoboranes through boron chelate compounds, namely, dialkyl-boryl[N-(5-tetrazolyl)amidinates].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2622–2624, November, 1987.  相似文献   
4.
Ab initio study of the adiabatic potential energy surface (PES) for 1,2,3-trifluorobenzene cation-radical was carried out by the ROHF, UHF, MCSCF, MP2, and DFT (B3LYP) methods with the 6-31G* basis set. The PES in question is a pseudorotation surface at all calculation levels. The pseudorotation barrier height does not exceed 3.2 kcal/mol, suggesting a possibility for its manifestations in experimental EPR spectra.  相似文献   
5.
A structure with a pyramidal -CF2 group is shown to desribe satisfactorily hyperfine interactions in CH2CF2 radical anions within the framework of the INDO method. The factors responsible for the substantial difference in the degree of spin density delocalization on F in CH2CF2 and C2F4 are analyzed.  相似文献   
6.
The ESR spectrum of 1,3,5-trifluorobenzene radical anion was obtained for the first time using optically detected ESR spectroscopy. Experimental data and results of a quantum chemical study of the potential energy surface (density functional theory B3LYP and BHHLYP methods) are indicative of fast interconversions between nonplanar conformations of this radical anion.  相似文献   
7.
The possibility of a localized growth of materials from amorphous hydrogenated carbon by the barrier-discharge treatment of a benzene vapor mixture with argon has been shown. Two types of material are produced, the “columnar” black entities of ~100 μm in diameter and 2 mm in height and the “polymeric patterns” as “honeycombs” of ~ 4–6 mm diameter with a clearly defined boundary in the form of the “swell” as high as 100 μm. The structure and composition of the materials and their growth kinetics have been investigated.  相似文献   
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9.
The oxidation of cyclohexene mixtures with hexane, octane, decane, and cyclohexane was studied in a dielectric-barrier discharge reactor. It was shown that a decrease in the partial pressure of cyclohexene in the mixture resulted in a significant increase in the yield of cyclohexene oxide to 75%, with the composition of oxidation products being the same as in the oxidation of individual compounds. A plausible mechanism of the reaction is proposed.  相似文献   
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