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1.
V. M. Tapilin 《Journal of Structural Chemistry》1994,35(1):13-20
The Slater approximation for atomic electron energies is employed to calculate the electronic structure of the Ir(111) surface.
The results are used to estimate the shift of the 4f7/2 level on the surface relative to its position in the volume. The electron state densities in the neighborhood of the center
of the surface Brillouin zone (SBZ) are compared with photoelectronic spectra for emission normal to the Ir(111) surface.
On this basis, the accuracy of this approximation is estimated.
Institute of Catalysis, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 1, pp. 17–24, January–February, 1994.
Translated by O. Kharlamova 相似文献
2.
J. -J. Borras-Almenar E. Coronado B. S. Tsukerblat A. V. Palii A. V. Babich 《Journal of Structural Chemistry》1994,35(4):454-464
Electronic and adiabatic vibronic states of d1-d1-d2 trimeric clusters are considered in terms of the many-electron theory of mixed-valence states. The initial model includes
two d-orbitals on each center and allows for Heisenberg and double exchange, asymmetry of the system, and vibronic coupling
with local shifts of ligands. Influence of distortions in the trimers on the structure of tunnel-exchange states, on ferro-or
antiferromagnetism of the clusters, and on the form of the adiabatic potential is examined.
State University, Moldova Republic. Valencia University, Spain. Institute of Chemistry, Academy of Sciences, Moldova Republic.
Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 4, pp. 35–45, July–August, 1994.
Translated by L. Smolina 相似文献
3.
V. P. Koropchanu F. G. Paladii S. I. Boldyrev V. Ya. Gamurar' 《Journal of Structural Chemistry》1996,37(5):707-712
The tunnel states of square-planar bielectron transfer dn-dn-dn+1-dn+1 (n=0–4) clusters are considered. The nature of the ground spin state is revealed in the limiting case of a strong double
exchange. It is shown that the magnetic properties of these systems radically differ from those of clusters with one migrating
electron (hole) and tetrameric tetrahedral bielectron transfer clusters.
Moldova State University. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 5, pp. 826–833, September–October, 1996.
Translated by I. Izvekova 相似文献
4.
The CH3OCOCl molecule is calculated by ab initio methods using the split-valence basis sets at RHF/3-21G//RHF/3-21G, RHF/6-31G*//RHF/6-31G*, and RHF/6-311G*//RHF/6-31G* levels of theory and in the MNDO approximation. The optimized geometry of the molecule is consistent with the experimental
data. The populations of the p-AOs of this molecule and the MO compositions show that the electron distribution in this molecule
should be interpreted without considering the conjugation between the lone electron pairs of the Cl or O atoms and the π-electron
system of the carbonyl group. The asymmetry parameters of the electric field gradient on the35Cl nucleus were calculated using the Cl p-AO populations and compared with the corresponding experimental value.
Instite of Technical Chemistry, Ural Branch, Russian Academy of Sciences. Translated fromZhurnal Struktumoi Khimii, Vol. 37, No. 4, pp. 646–651, July–August, 1996.
Translated by I. Izvekova 相似文献
5.
In the ESR spectra of electron-iradiated diamonds of different types, a region near g=4.3 is analyzed. Forbidden transitions
ΔM=2 of R1 and R2 have been found for some centers with S=3/2 in diamonds of type Ic. For the forbidden transitions of R1,
the hyperfine structures in four coordination spheres of13C have been investigated. Based on the results obtained it is shown that the R1 center is a semivacancy pair. For the forbidden
transitions of the R2 center, intensity ratios and hfi constants, which are unusual in vacancy type defects, have been found.
The observed set of centers with S=3/2 for irradiated diamonds of type 1c is explained by electron transfer from the donor
nitrogen atom to the known radiation centers with S=1.
Decreased.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurmal Strukturnoi Khimii, Vol. 36, No. 4, pp. 690–696, July–August, 1995.
Translated by L. Smolina 相似文献
6.
The standard entropies theoretically calculated for 40 haloalkanes and haloarenes adsorbed on graphitized thermal carbon black
were compared with those determined from the adsorption-chromatographic data. It was found that a molecular model of an ideal
two-dimensional gas is a sufficiently good approximation in all the cases. For a number of systems, agreement can be improved
by taking into account the vibrations of the center of the molecular mass relative to the surface.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2173–2176, December, 1997. 相似文献
7.
O. V. Sizova V. I. Baranovskii N. V. Ivanova A. I. Panin 《Journal of Structural Chemistry》1996,37(4):525-536
The electronic spectra of the [Ru(NH3)5pz]2+, [Ru(NH3)5pz]3+, and [Ru(CN)5pz]3− complexes are calculated by the CI INDO method. The effect of solvation on the spectra is considered in a point charge approximation
and in terms of the parametric model of a charged sphere enveloping the metal fragment. Interrelation of these approaches
is discussed. Data on the molecular electrostatic potentials created by the complexes are presented to substantiate the models.
St. Petersburg State University. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 4, pp. 603–618, July–August, 1996.
Translated by I. Izvekova 相似文献
8.
A quantum-chemical investigation into the location and form of solitons in the cations of unsymmetrical polymethine systems
was undertaken. It was shown that the introduction of one terminal group (electron-donating or electron-accepting) with intrinsic
level outside the energy gap of the main chromophore leads to displacement of the charge and geometric waves without substantial
distortion of their form; the introduction of an amino group with a high level for the unshared electron pair is accompanied
by displacement of the solitons to the end of the conjugation chain, so that half of the soliton wave projects onto the molecule.
In unsymmetrical polymethine cations with two nitrous groups the geometric soliton is closer to the less basic residue; replacement
of one terminal residue by a methoxy group moves the position of the soliton to the end of the chromophore.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 44, No. 4, pp. 221–227, July–August, 2008. 相似文献
9.
G. N. Ten V. V. Nechaev V. I. Berezin V. I. Baranov 《Journal of Structural Chemistry》1997,38(2):262-267
The vibrational spectra of adenine and its deuterium-substituted analogs are calculated in the valence force field approximation.
The frequencies and forms of normal vibrations of the molecule at 1700–300 cm-1 are interpreted.
Translated fromZhumal Struktumoi Khimii, Vol. 38, No. 2, pp. 324–333, March–April, 1997. 相似文献
10.
Using ESR and optical spectroscopy we showed that the blue coloring is imparted to natural apatites by SO
3
−
radicals and the green coloring is due to SiO
3
−
radicals complexed with rare earth ions, SiO
3
−
-(Ce3++K). The role of U4+ and Th4+ isomorphous actinide ions in the process of color center formation is investigated.
United Institute of Geology, Geophysics, and Mineralogy, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Struktumoi Khimii, Vol. 36, No. 1, pp. 89–101, January–February, 1995.
Translated by L. Smolina 相似文献
11.
V. P. Koropchanu F. G. Paladii S. I. Boldyrev V. Ya. Gamurar' 《Journal of Structural Chemistry》1996,37(3):398-408
Tunnel-exchange states of tetrahedral tetrameric clusters dn-dn-dn+1-dn+1 with double transfer are considered to calculate the energy levels and wave functions. A method based on the second quantization
technique and group-theoretical approach is developed. The nature of the ground spin state of the above systems is determined.
It is shown that the structures have magnetic properties that radically differ from the properties of clusters with one migrating
electron (hole).
Moldova State University. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 3, pp. 458–470, May–June, 1996. 相似文献
12.
A. S. Vorob'ev I. I. Furlei A. Sh. Sultanov E. A. Burmistrov 《Russian Chemical Bulletin》1997,46(10):1797-1799
Negative-ion mass spectrometry in the mode of resonance capture of electrons and photoelectron spectroscopy in combination
with quantum-chemical calculations showed that the formation of the resonance states of negative molecular ions in the reaction
of electrons with molecules of the mechanism of intershell Feshbach resonance with the consecutive excitation of an electron
from several higher occupied MO to one vacant MO. In a low-energy region, the resonance at 1.4 eV is a resonance of form and
the resonance at 3–4 eV is the usual electron exciting Feshbach resonance with a parent triplet state (π.π*)3. The one and the same vacant π*CC MO is “active” in all the resonances mentioned.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1892–1894, October, 1997. 相似文献
13.
A. V. Babich J. J. Borras-Almenar E. Coronado A. V. Palii B. S. Tsukerblat 《Journal of Structural Chemistry》1995,36(4):593-605
The statistical distribution of electron density in a C2v one-electron trimeric mixed-valence cluster is considered in terms of the Piepho-Krausz-Schatz vibronic model using the adiabatic
approximation. Conditions are revealed under which the lower branch of the adiabatic potential shows three minima, each corresponding
to predominant localization of the electron on one of the three ionic centers. It is shown that when the symmetry of the system
is disturbed, the potential has two minima, with the system localized on one of two equivalent centers at either minimum.
Conditions are considered under which these minima merge into one minimum, which corresponds to delocalization of the electron
over a pair of ions, i.e., partial delocalization. For a D3h symmetric trimer, it is demonstrated that in the region of transfer parameters and vibronic couplings, where the localized
and completely delocalized states coexist, even with insignificant distortions there are only three localization minima, and
the central minimum, which corresponds to a completely delocalized state, vanishes.
Valencia University, Spain. Institute of Chemistry, Academy of Sciences, Moldova Republic. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 4, pp. 654–666, July–August, 1995
Translated by I. Izvekova 相似文献
14.
L. N. Mazalov S. V. Trubina I. M. Oglezneva N. A. Kryuchkova O. V. Tarasenko V. L. Varand T. E. Kokina S. V. Larionov 《Journal of Structural Chemistry》2005,46(3):542-545
X-ray photoelectron and voltammetry studies of the charged state of the metal atom in nickel(II) chelate complexes with ligands
containing CS
2
−
and PS
2
−
groups and in heteroligand complexes on their basis were carried out. It is shown that the degree of formal oxidation of
the nickel atom in the complexes corresponds to Ni(II). In the case of heteroligand complexes, addition of nitrogen heterocycles
causes an increase in the electron density on the atoms of the coordination center. Theoretical data obtained in ab initio quantum chemical model calculations correlate with the experimental results.
Original Russian Text Copyright ? 2005 by L. N. Mazalov, S. V. Trubina, I. M. Oglezneva, N. A. Kryuchkova, O. V. Tarasenko,
V. L. Varand, T. E. Kokina, and S. V. Larionov
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 3, pp. 554–557, May–June, 2005. 相似文献
15.
M. V. Muftakhov R. V. Khatymov V. A. Mazunov V. N. Odinokov I. V. Galyautdinov 《Russian Chemical Bulletin》2000,49(4):713-716
The peculiarities of dissociative electron capture by 20-hydroxyecdysone molecules with the formation of fragment negative
ions were studied. In the region of high electron energies (5–10 eV), processes of skeleton bond rupture are accompanied by
the elimination of H2O and H2 molecules. In the region of thermal energies of electrons (≈0 eV), the mass spectrum is formed mainly by the [M−nH2O].− (n=1–3) and [M−H2−nH2O].− (n=0−3) ions that are generated exclusively by the rearrangement.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 709–712, April, 2000. 相似文献
16.
The inductive and resonance effects of silicon-, germanium-, tin-, and lead-containing and some organic substituents on the
HOMO energies (E
HOMO) for 43 monosubstituted andp-disubstituted benzene derivatives were analyzed in the Koopmans approximation. A linear dependence between the perturbation
energy δE and the resonanceσ
R
+
parameters of the substituents was established. The Koopmans approximation is a rough approximation for the compounds studied,
since to provide for its rigorous fulfilment, the δE values must depend on the σ
R
0
parameters of the substituents. The principal regularities of increasing the σ,π-conjugation between the organoelement substituents
and the π-system caused by a positive charge on the benzene ring were established.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 70–75, January 1997. 相似文献
17.
Double exchange in polynuclear mixed-valence clusters. 1. General solution of the electronic problem
J. J. Borras-Almenar R. Jorge S. I. Klokishner E. Coronado S. M. Ostrovskii A. V. Palii B. S. Tsukerblat 《Journal of Structural Chemistry》1996,37(5):689-698
The problem of calculating the electronic energy spectra of mixed-valence clusters with one “extra” electron (dn-dn...dn+1) or hole (dn+1-dn+1...dn) delocalized in the paramagnetic cores of transition metals is solved. Unlike the available particular solutions, which are
restricted to small numbers of ions and electrons, the solution proposed in this work is general and is suitable for many-electron
systems of arbitrary numbers of nuclei and arbitrary symmetries. The new microscopic approach to the double exchange problem
is based on the combination of the sequential (“chain”) scheme of spin coupling and angular momentum method. In terms of this
approach, an analytical dependence of the matrix elements of the double exchange, Heisenberg exchange, and vibronic interaction
on all spin quantum numbers is obtained. The final equations contain only the 6j symbols and are free of the higher-order
nj symbols, which obstructed the solution of the double exchange problem in previous works.
Valencia University, Spain. Bordeaux University, France. Moldova State University. Institute of Chemistry, Academy of Sciences,
Moldova Republic. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 5, pp. 805–815, September–October, 1996.
Translated by I. Izvekova 相似文献
18.
This paper gives the results of quantum chemical MINDO/3 calculations of carbon monoxide adsorption on the ZnO polar (0001)
surface. The energetically most favorable one-center adsorption of carbon monoxide on the ZnO (0001) surface occurs by the
electron density transfer from the lone electron pair of CO carbon to the vacant orbital of the Zn
3C
2+
cation. The calculated heat of CO adsorption, dependent on the type of covering, and the stretching frequency υCO are in good agreement with the available experimental data.
Institute of Catalysis, Siberian Branch, Russian Academy of Sciences. Ruhr University, Bochum, Germany. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 1, pp. 12–16, January–February, 1994.
Translated by L. Smolina 相似文献
19.
20.
The vibrational structure of the electron transition to the second singlet excited state of pyridine N-oxide has been studied.
The frequency of the 0–0 transition is 34502 cm−1. A computer-aided technique for the assignment of the frequencies of the normal vibrations of polyatomic molecules in the
excited electronic states is proposed. The frequencies of the totally symmetric vibrations of pyridine N-oxide in the second
singlet electronically excited state are assigned.
N. G. Chernyshevskii Saratov State University. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 2, pp. 350–355, March–April, 1995.
Translated by I. Izvekova 相似文献