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1.
A. I. Pavlyuchko 《Journal of Structural Chemistry》1995,36(2):204-209
A method of variational solution of anharmonic vibration problems using a mixed Morse—anharmonic basis is proposed. The basis
functions are the products of the Morse oscillator eigenfunctions for vibrations of peripheral bonds, the harmonic oscillator
eigenfunctions for almost harmonic skeletal and deformation vibrations, and the anharmonic basis functions for essentially
anharmonic skeletal and deformation vibrations. The anharmonic basis wave functions are taken as a linear combination of the
Morse and harmonic oscillator eigenfunctions. The introduction of the combined Morse—anharmonic functions allows one to factorize
the solution of a problem into a series of individual blocks according to the fragmentary structure of molecules.
Volgograd Pedagogical University. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 2, pp. 231–238, March–April, 1995.
Translated by I. Izvekova 相似文献
2.
K. V. Mikhailova 《Journal of Structural Chemistry》1995,36(2):265-270
Correct assignment of calculated and experimental frequencies, as well as corservation of the initial assignment in case of
a random coincidence of two frequencies during the solution of an inverse spectral problem, are important problems in spectroscopy
of polyatomic molecules. Vibrations are classified according to their form, which is thought to be a more reliable basis for
assignment than frequency. We offer a PC program to determine the type of vibrations according to their form (obtained by
solving a direct vibrational problem) in a given system of vibrational basis set functions. Optimization of systems of basis
set functions for molecules with six-membered rings is discussed.
L. Ya. Karpov Physicochemical Scientific Research Institute. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 2, pp. 298–303, March–April, 1995.
Translated by L. Smolina 相似文献
3.
4.
É. N. Yurchenko 《Journal of Structural Chemistry》1996,37(2):217-223
The paper describes methods for determining the force fields of large sets of molecules which share the common property that
in their constituent groups of molecules the equivalent force constants always change monotonically with the properties of
substituent atoms belonging to the same subgroup of the periodic table. The force fields of the CH4−nXn (n=0–4, X=F, Cl, Br, I) molecules of the methane series are obtained. The applications of these force fields are discussed.
In particular, they can serve as a basis for a data bank of the force fields of fragments suitable for constructing the force
fields of more complex molecules.
Russian Scientific Center “Applied Chemistry”, St. Petersburg. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 2, pp. 250–256, March–April, 1996.
Translated by I. Izvekova 相似文献
5.
L. A. Gribov 《Journal of Structural Chemistry》1994,35(4):533-541
Major problems in using some key notions of the theory of structure, such as bond length and potential function parameters,
are discussed on the basis of the general complementarity principle formulated by Bohr. It is shown that the use of this principle
and model representations, indispensable in microworld studies, inevitably involves subjectivism arising in the solution of
inverse problems, and leads to the violation of the requirement of reason.
Vernadskii Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 4, pp. 123–134, July–August, 1994.
Translated by O. Kharlamova 相似文献
6.
Data selection techniques are considered for structure generation in structure elucidation systems using molecular spectroscopy
databases. The starting data are sets of microfragments and connected structural fragments obtained from computer-aided analysis
of mass, IR, and NMR spectra. Selection of fragments that do not isomorphically fit in larger fragments mostly leads to correct
results with fewer output structures anddemands less computer time.
Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 2, pp. 46–53, March–April, 1994.
Translated by L. Smolina 相似文献
7.
Experimental data (obtained by the authors and taken from the literature) on the structure and conformations of carbonyl molecules
in the ground and lower excited electronic states are presented. The structure of carbonyl fragments, the orientation of substituent
groups, the energy of the molecules in excited states, and the potential functions of the internal rotation and inversion
are considered. The structural similarities of the molecules are discussed.
M. V. Lomonosov Moscow State University, Chemical Faculty. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 2, pp. 269–285, March–April, 1995.
Translated by I. Izvekova 相似文献
8.
S. B. Érenburg L. N. Mazalov N. V. Bausk M. K. Drozdova 《Journal of Structural Chemistry》1994,35(4):517-522
SKα, SKβ, ClKβ, ClKβ, and PdLβ2 X-ray fluorescent and PdK EXAFS spectra were obtained for some organic solutions of dialkyl sulfide complexes with palladium
chloride. Solvent effects on the electronic and spatial structure of complexes in solution are discussed. In the benzene solution
of [PdCl22(C6H13)2S], complex molecules interact with solvent molecules along a coordinate that is perpendicular to the plane of the complex
molecule.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurmal Strukturnoi Khimii, Vol. 35, No. 4, pp. 105c111, July–August, 1994.
Translated by L. Smolina 相似文献
9.
This paper studies the formation of a stable anion pair as a result of cluster interactions with water molecules (the number
of molecules n=4, 6, 8, and 14). The hydration shells of the clusters obtained in a preliminary calculation are destructed
to form closed chains of properly oriented water molecules in the space between the anions. The type of the resulting structure
depends on the number of shared water molecules. The character of stabilization of the anion pair, determined by calculating
different energy terms, also changes as n increases. The cyclic structures obtained in the region of the anion pair differ
considerably from the structure of isolated Cl− (H2O)n clusters and that of the aqueous solution of NaCl. The capture of water molecules by the anion pair is manifested in the
nucleation of industrial steam.
Institute of Thermal Physics, Ural Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 2, pp. 289–298, March–April, 1996.
Translated by L. Smolina 相似文献
10.
V. E. Kuzmin N. S. Novikova T. A. Sidelnikova L. P. Trigub 《Journal of Structural Chemistry》1994,35(4):471-477
The use of topological indices to reveal the relationship between molecular structure and mesomorphous properties is discussed.
Mathematical models for classification of mesophase types are proposed. The effect of molecular structure and attractive ability
on phase transition temperatures is described. Examples of using correlation equations to predict the properties of 2,5-disubstituted
1,3-dioxanes are given.
A. V. Bogatskii Physicochemical Institute, Ukrainian Academy of Sciences. Translated fromZhurnal Struktumoi Khimii, Vol. 35, No. 4, pp. 53–60, July–August, 1994.
Translated by L. Smolina 相似文献
11.
The absorption spectra of decapentaene are analyzed and calculated using the available efficient methods of calculating the
matric elements of the vibronic problem, a new parametric method for determining the potential surfaces of excited molecules,
and a fragmentation approach to the design of molecular models. Good agreement for the fine vibrational structure of the calculated
and experimental spectra (differences between the main band frequencies and intensities less than 20 cm−1 and 10%, respectively) is obtained without correcting the parameters of the method. The mechanisms of excitation-induced
structural changes in linear polyenes and the effect of bond angle changes on the vibrational structure of the spectrum are
revealed. A new interpretation of the absorption spectrum of decapentaene in an argon matrix is proposed [J. Mol. Spectrosc.,114, 54–59 (1985)]. It is shown that the parametric method allows quantitative prediction of fine structure for the vibronic
spectra of complex molecules.
K. A. Timiryazev Moscow Agricultural Academy. Translated fromZhurnal Strukturmoi Khimii, Vol. 37, No. 6, pp. 1031–1039, November–December, 1996.
Translated by I. Izvekova 相似文献
12.
I. S. Perelygin 《Journal of Structural Chemistry》1997,38(2):218-226
The structure and shape of bands in the Raman vibrational spectra of polar molecules in liquids are analyzed. The possibility
of using these data to examine interactions of molecules as well as their vibrational and orientational dynamics is shown.
Translated from Zhumal Struktumoi Khimii, Vol. 38, No. 2, pp. 270–281, March–April, 1997. 相似文献
13.
A model of concentration transition “ions and complexes in a water structure → ionic and ionicaqueous clusters → polymer structures
of salt and crystal hydrate melts” is suggested. The appearance of cluster nanostructures outside the first zone of a waterlike
structure is regarded as a general characteristic of solutions. The characteristics of solutions, phase equilibria, and salts
of complex composition are interpreted based on this model. Investigation of the complex dielectric constant of electrolytic
solutions in the SHF and EHF bands (7–119 GHz) at high concentrations showed that there are two dispersion regions in which
the relaxation times differ by a factor of 5–10. Relaxation processes are separated, the numbers of molecules in hydration
shells are calculated, and relaxation times are determined for bulky tetrahedral water with hydration shells of ions, for
clusters, and for ionicaqueous polymer chains. It is shown that the two structure subsystems of water molecules in concentrated
solutions may be described using the limited rotator/generalized diffusion molecular model.
Translated fromZhumal Strukturnoi Khimii, Vol. 39, No. 5, pp. 851–863, September–October, 1998. 相似文献
14.
V. E. Kuzmin V. A. Chelombitko I. V. Yudanova I. B. Stelmakh I. S. Rublev 《Journal of Structural Chemistry》1998,39(3):452-456
Stereoanalysis of molecules by partitioning a spatial structure into a system of simplices is described in detail. Potentialities
of simplex representation of molecules in defining stereochemistry are demonstrated for chiral structures of various complexity
and planar unsaturated molecules (“two-dimensional stereochemistry”). A concept of “stereochemical charge” is introduced.
A. V. Bogatskii Physicochemical Institute, Ukrainian Academy of Sciences. Odessa State University. Translated fromZhurnal Strukturnoi Khimii, Vol. 39, No. 3, pp. 553–558, May–June, 1998. 相似文献
15.
L. M. Babkov O. V. Gorshkova N. A. Golovina G. A. Puchkovskaya I. N. Khakimov 《Journal of Structural Chemistry》1995,36(2):302-308
Polymorphism and the structure of mesomorphous states of long-chain aliphatic compounds (LAC) have been studied by vibrational
spectroscopy (theory, experiment) using calorimetry, polarizing microscopy (PM), and X-ray diffraction (XRD) analysis as auxiliary
methods. LAC are represented by homologous series of alkyl- and alkoxybenzoic acids, alkylcyclohexanecarboxylic acids, their
completely or partially fluoroalkyl-substituted analogs, and 4-cyano-4′-(n-alkoxy)biphenyls. The studies were performed at
77–500 K. IR absorption and Raman spectra were measured at 30–4000 cm−1. The compounds are characterized by conformational polymorphism. The molecules and their H-complexes undergo structural rearrangements
during phase and conformational transitions. In the course of the rearrangements, alkyl and fluoroalkyl radicals (AR and FAR)
are twisted, and carboxyl groups are disordered. The rearrangements dictate the structure of mesophases, which are mostly
formed of H-complexes consisting of dimers, monomers, and open associates.
N. G. Chernyshevskii Saratov State University. Institute of Physics, Ukrainian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 2, pp. 338–344, March–April, 1995.
Translated by L. Smolina 相似文献
16.
A new model based on certain physical concepts of interatomic interactions is proposed for simulating the volume characteristics
of molecules that allow reliable estimations of the densities of substances and solutions. The model is used to calculate
the solution densities for six substances within wide concentration ranges.
Chelyabinsk State University. Translated fromZhurmal Strukturnoi Khimii, Vol. 36, No. 5, pp. 823–827, September–October, 1995.
Translated by I. Izvekova 相似文献
17.
Yu. I. Naberukhin V. A. Luchnikov G. G. Malenkov E. A. Zheligovskaya 《Journal of Structural Chemistry》1997,38(4):593-600
The local structure of the molecular- dynamic model of water (729 particles at 300 K) is analyzed by isolating molecules whose
surroundings differ slightly in configuration from a regular tetrahedron. These molecules are not randomly distributed in
space but form nanometer clusters having a fractal structure. In these clusters, molecules are less mobile than the model
molecules in general;their self- correlation function of rate and the density of vibrational states also differ from the average characteristics of
the system.
Translated fromZhumal Strukturnoi Khimii, Vol. 38, No. 4, pp. 713–722, July–August, 1997. 相似文献
18.
V. N. Piottukh-Peletskii T. F. Bogdanova B. G. Derendyaev 《Journal of Structural Chemistry》1996,37(2):323-331
This paper studies the possibility of revealing various fragments (not given beforehand) in a structure by analyzing the structures
selected from the database as a result of a retrieval by the IR spectrum of the compound; the fragments range from those with
two nodes (e.g., C=O, C=C) to those with some limited number of connected nodes. It is shown that complete fragment sets reflecting
the composition of the selected compound (fragment compositions) contain the information about the set of bonded fragments
of the compound. Various factors affecting analysis of the compiled list of fragments are considered using a particular example.
Different techniques for revealing structural information are discussed.
Scientific and Technical Center of Chemical Informatics, Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian
Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 2, pp. 368–378, March–April, 1996.
Translated by L. Smolina 相似文献
19.
Yu. I. Vesnin 《Journal of Structural Chemistry》1995,36(4):655-660
Published experimental data on the dependence of the properties of crystal substances on crystal size are discussed. The dependence
is of the same form for different properties and different crystal substances. When the crystal diminishes in size, its properties
remain constant until the size decreases to 10−5–10−6 cm; smaller crystals considerably change their properties. It is shown that the currently available experimental data are
sufficient to substantiate the notion of an “elementary unit of a solid crystal” (“crystal quantum”). The elementary unit
of a crystal is regarded as a basis for the secondary structure (macrostructure) of a solid and an elementary carrier of its
“crystal” properties. Due to this notion, we can interpret the vast experimental material on the real structures and properties
of solids from a single viewpoint.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 4, pp. 724–730, July–August, 1995.
Translated by L. Smolina 相似文献