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111.
112.
Evgueni Vassiliev 《Annals of Pure and Applied Logic》2003,120(1-3):103-149
For a supersimple SU-rank 1 theory T we introduce the notion of a generic elementary pair of models of T (generic T-pair). We show that the theory T* of all generic T-pairs is complete and supersimple. In the strongly minimal case, T* coincides with the theory of infinite dimensional pairs, which was used in (S. Buechler, Pseudoprojective strongly minimal sets are locally projective, J. Symbolic Logic 56(4) (1991) 1184–1194) to study the geometric properties of T. In our SU-rank 1 setting, we use T* for the same purpose. In particular, we obtain a characterization of linearity for SU-rank 1 structures by giving several equivalent conditions on T*, find a “weak” version of local modularity which is equivalent to linearity, show that linearity coincides with 1-basedness, and use the generic pairs to “recover” projective geometries over division rings from non-trivial linear SU-rank 1 structures. 相似文献
113.
L. A. Gribov 《Journal of Applied Spectroscopy》2006,73(3):323-327
The concept of the adiabatic approximation is introduced from a few new standpoints, and the conditions are refined under
which we can assume that the total energy of an electronic-vibrational (vibronic) state is the sum of the energies of the
“electronic” and the “nuclear” problems and the wave function is represented as the product of the corresponding functions.
An expression exactly corresponding to such an approximation is considered for the optical transition matrix element, and
its individual terms are analyzed for any change in the geometric structure of the molecule upon optical excitation.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 3, pp. 290–293, May–June, 2006. 相似文献
114.
115.
L. A. Gribov 《Journal of Structural Chemistry》1996,37(6):847-854
The problem of calculating the probability of optical transitions between the topological isomers of polyatomic molecules
is considered. It is shown that the adiabatic approximation can be extended to this case. It is suggested that under certain
conditions an “unoccupied” isomeric state can be populated or light-stimulated accumulation of one isomer can be achieved.
This opens up prospects for designing molecular elements for computer memory.
V. I. Vernadskii Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 6, pp. 994–1005, November–December, 1996.
Translated by I. Izvekova 相似文献
116.
A. N. Pankratov S. P. Mushtakova L. A. Gribov 《Theoretical and Experimental Chemistry》1985,21(1):79-83
Using the CNDO/2 method, we have calculated the valence electron density distribution in molecules of diphenylamine and its 13 derivatives with the substituents COOH, NO2, OCH3 on the aromatic rings of ionized forms of some diaryl amines, and also 4-amino- and 4-amino-4-adnitro substituted compounds with bridge groups NH, O, S, CH2, CH=CH and analogous diphenyl derivatives. We have shown that independently of the nature of the bridge group, the principle of uncoupling of the aromatic rings is basically retained. Strong long-range effects of the substitutents along the chain of chemical bonds are not apparent. We have calculated the electrostatic molecular potential of the indicated compounds. We have established correlations between the electrostatic molecular potential and the protonization constants, the oxidation-reduction potentials of diarylamines; and also between the electrostatic molecular potential and the reaction rate constant for acylation of primary bridged amines at the amino group.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 21, No. 1, pp. 84–88, January–February, 1985. 相似文献
117.
In continuing our research on solid-state organic photochemistry, we have been investigating the phenomenon of reactivity in stages. In this study we present new examples where the photochemical reactivity changes discontinuously at some point in the conversion. In these instances, the reaction course of the solid differs from that in solution. One example is the reaction of 2-methyl-4,4-diphenylcyclohexenone, where an unusual reaction course was encountered in the solid state; and, of two possible mechanisms, one was established by isotopic labeling. A second case is that of 4,5,5-triphenylcyclohexenone. The solid-state reaction of this enone was found to give a new photochemical transformation, the Type C rearrangement, a process that involves a delta to alpha aryl migration. In the case of 3-tert-butyl-5,5-diphenylcyclohexenone the Type C rearrangement occurred even in solution. The stage behavior was investigated using X-ray analysis and Quantum Mechanics/Molecular Mechanics computations. This permitted us to determine the sources and details of the stage phenomenon. The analysis revealed how a product molecule as a neighbor affects reactivity. The computations were employed to follow the course of a solid-state reaction from reactant through the succeeding stages. Additionally, the Delta-Density Analysis was utilized to ascertain the electronic nature of molecular changes. Besides product composition changing with extent of conversion, the reaction quantum yield was found to change as one stage gave way to a succeeding one. 相似文献
118.
The construction algorithm is proposed for the internal rotation coordinates in polyatomic molecules. It is based on the properties of the matrix of kinematic coefficients when an excessive system of natural coordinates is introduced. The approximations providing the separation of variables are considered. The exact form of the kinetic energy operator is given. 相似文献
119.
Ekaterina V. Kuznetsova Evgueni N. Savinov Alexandre V. Vorontsov Panagiotis Smirniotis 《Reaction Kinetics and Catalysis Letters》2003,78(2):341-348
A Cu(OH)2/α-Fe2O3 photocatalyst is shown to be active in the gas phase oxidation of ethanol under visible light. The calculated initial quantum
efficiency of the ethanol photooxidation is 0.1-1%. However, ethanol is oxidized only into acetic acid, which deactivates
the catalyst.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
120.
É. B. Yagubskii M. L. Khidekel' I. F. Shchegolev L. I. Buravov B. G. Gribov M. K. Makova 《Russian Chemical Bulletin》1968,17(9):2013-2014
Conclusions For the first time complexes of arenechromium compounds with 7,7,8,8-tetracyanoquinodimethane were obtained.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2124–2125, September, 1968. 相似文献