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101.
Monika S. K. Fuchs Alexey M. Shor Notker Rsch 《International journal of quantum chemistry》2002,86(5):487-501
The parallel density functional program PARA GAUSS has been extended by a tool for computing solvent effects based on the conductor‐like screening model (COSMO). The molecular cavity in the solvent is constructed as a set of overlapping spheres according to the GEPOL algorithm. The cavity tessellation scheme and the resulting set of point charges on the cavity surface comply with the point group symmetry of the solute. Symmetry is exploited to reduce the computational effort of the solvent model. To allow an automatic geometry optimization including solvent effects, care has been taken to avoid discontinuities due to the discretization (weights of tesserae, number of spheres created by GEPOL). In this context, an alternative definition for the grid points representing the tesserae is introduced. In addition to the COSMO model, short‐range solvent effects are taken into account via a force field. We apply the solvent module to all‐electron scalar‐relativistic density functional calculations on uranyl, UO22+, and its aquo complexes in aqueous solution. Solvent effects on the geometry are very small. Based on the model [UO2(H2O)5]2+, the solvation energy of uranyl is estimated to be about ?400 kcal/mol, in agreement with the range of experimental data. The major part of the solvation energy, about ?250 kcal/mol, is due to a donor–acceptor interaction associated with a coordination shell of five water ligands. One can interpret this large solvation energy also as a compounded effect of an effective reduction of the uranyl moiety plus a solvent polarization. The energetic effect of the structure relaxation in the solution is only about 8 kcal/mol. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001 相似文献
102.
B. S. Fedorov M. A. Fadeev V. V. Arakcheeva L. S. Barinova L. T. Eremenko 《Russian Chemical Bulletin》1996,45(2):376-380
A general reaction of the transformation of the fluorodinitromethyl group into the fluoronitromethyl group by denitration upon treatment with Na2SO3 or KI in aqueous formaldehyde was found. A preparative method for synthesizing fluoronitroalcohols was developed on the basis of this reaction. 相似文献
103.
104.
This paper is concerned with the dynamics of vortex sources in a deformation flow. The case of two vortex sources is shown to be integrable by quadratures. In addition, the relative equilibria (of the reduced system) are examined in detail and it is shown that in this case the trajectory of vortex sources is an ellipse. 相似文献
105.
O. A. Buzanov V. M. Kanevskii V. N. Kornoukhov B. V. Nabatov V. V. Nabatov V. A. Fedorov 《Crystallography Reports》2013,58(6):883-888
The optical and spectral characteristics of isotopically enriched Czochralski-grown 40Ca100MoO4 single crystals have been investigated. This material is promising for detecting double neutrinoless β decay. The possibility and the technique of spectrophotometric monitoring of weak residual absorption near the intrinsic luminescence peak of this scintillation material, which is designed for developing new-generation detectors of elementary particles, are considered. 相似文献
106.
The problem on acoustic-wave reflection from the boundary of a gas?droplet mixture is considered. For the interface between the pure gas and the gas?droplet mixture at a wave inclined incidence, a nonmonotonic dependence of the reflectance on the volume content of droplets is established. The values of the critical wave-incidence angle and the volume content of inclusions at which the reflectance vanishes are found and illustrated. The possibility of occurrence of the lowest reflectance in dependence on the frequency of perturbations in a certain interval of the wave-incidence angle related mainly to the difference in the densities of the gas-droplet mixture and the pure gas is shown. 相似文献
107.
V. P. Matveenko N. V. Sevodina A. Yu. Fedorov 《Journal of Applied Mechanics and Technical Physics》2013,54(5):841-846
The stress state in adhesive lap joints with various geometric shapes of spew fillet is studied. It is noted that the applied design models of the considered problem include singular points at which infinite stress values are possible if one uses the linear elasticity theory to calculate the stress state. Based on the conclusions of the solution of the geometry optimization problem in the vicinity of the singular points of elastic bodies, variants of the geometry of spew fillet, which provide the most significant decrease in the concentration of stresses in adhesive lap joints, are proposed. 相似文献
108.
109.
Fedorov A. N. Samoilenko D. E. Shafeeva M. V. Abzianidze V. V. Trishin Yu. G. 《Russian Journal of General Chemistry》2018,88(9):1948-1950
Russian Journal of General Chemistry - The action of sulfur diethylaminotrifluoride on 19β,28-epoxyoleanan-3-ol (allobetulin) causes dehydration of the terpenoid and isomerization of the ring... 相似文献
110.
Inside Back Cover: Synthesis and Isolation of the Titanium–Scandium Endohedral Fullerenes—Sc2TiC@Ih‐C80, Sc2TiC@D5h‐C80 and Sc2TiC2@Ih‐C80: Metal Size Tuning of the TiIV/TiIII Redox Potentials (Chem. Eur. J. 37/2016)
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