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The effect of rotation of ions or molecules on the NQR frequencies of nuclei in adjacent ions is considered in the framework of the theory of Chihara (ref. 1). The theory provides an adequate explanation of the temperature dependence in [Ca.6H2O] [SnCl6], but fails to explain details of pressure dependence measurements on NH4ReO4. 相似文献
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G. K. Semin E. V. Bryukhova A. M. Raevskii 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(8):1352-1354
For the crystallographically Inequivalent positions of the bromine atoms in CBr4, there exists an equation that relates the frequencies v of 79Br NQR to their field constants α = dv/dE z . This equation can be used to determine the strength of the local electric fields. 相似文献
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G. K. Semin E. N. Tsvetkov T. L. Khotsyanova E. V. Bryukhova 《Russian Chemical Bulletin》1999,48(5):906-913
Regularities of transmission of the effect of equatorial and axial substituents were established for a number of chlorine-containing
organic compounds of pentatalent phosphorus using35Cl NQR spectra. The field constants of35Cl NQR frequencies of the chlorine atoms participating in the P−Cl bond were estimated for a series of tetrahedral phosphorus
ions. The35Cl NQR frequencies of chlorine atoms in tetracoordinated ions of pentavalent phosphorus and in analogous isoelectronic silicon
compounds are related by a linear dependence.
Deceased
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 915–922, May, 1999. 相似文献
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O. V. Shishkin V. B. Zarkhin S. M. Desenko V. D. Orlov T. V. Timofeeva S. V. Lindeman Yu. T. Struchkov 《Theoretical and Experimental Chemistry》1993,28(4):262-264
The effect of alkyl substituents at atoms of double bonds on the conformation of the 1,3-cyclohexadiene ring was studied using a molecular-mechanics method. It was shown that the introduction of substituents results only in a change of the degree of ring puckering. It is concluded that there is equilibrium between flattening and unflattening factors, which then governs the constancy of the ring conformation.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 28, No. 4, pp. 334–337, July–August, 1992. 相似文献
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G. K. Semin E. V. Bryukhova V. M. Burbelo 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2010,84(1):141-142
An equation relating 35Cl NQR frequencies toinverse spin-lattice relaxation times was found for HGeCl3 crystalline phases. The equation was used to identify shortand long-range order contributions to the NQR frequency in the
environment of the resonance chlorine atom. Changes in the strength of local electric fields caused by the crystal field were
determined. 相似文献
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SCF MOLCAO calculations in the CNDO/2 approximation (valency sp basis) are presented for organic, heteroorganic, and inorganic chlorine compounds in the XCl series. Satisfactory correlations are obtained between the calculated charges on the Cl atoms, the populations of the p orbitals, and the numbers of unbalanced electrons on the one hand with the observed 35Cl NQR frequencies for the corresponding compounds in the XXXCCl and XCl series. These indicate that the Townes-Daly approximation in NQR spectroscopy is completely applicable even in the quantitative evaluation of chlorine-atom electron-density distributions in molecules.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 22, No. 1, pp. 26–31, January–February, 1986. 相似文献
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S.P. Basavaraju N. Devaraj A. Indumathy K.R. Sridharan J. Ramakrishna 《Journal of solid state chemistry》1983,47(2):236-238
Chlorine NQR in 2,6-dichloropyridine has been investigated in the temperature range 77 K to room temperature and a single resonance line has been observed throughout. Using this data, torsional frequencies of the molecule have been evaluated on the basis of both the Bayer theory and the modified Bayer theory incorporating Tatsuzaki correction. 相似文献
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The preferred conformation of solidphase R4benzylidene3,4dichloroaniline molecules has been established by nuclear quadrupole resonance (NQR) combined with quantum chemical calculations. The conformational effect of substitutes reported previously is proved. The rotation angle of the plane of the aniline ring with respect to the plane of the azomethine bond is given. 相似文献