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Dft study of donor-acceptor complexes of the non-transition and transition elements by nbo approach // Tomsk State Pedagogical University Bulletin. 2000. Issue 9 (25). P. 3-9

The calculations clearly show that the calculated by B3LYP/II and B3LYP/3-21G* 35CI frequencies correlate with the experimental values are the same. On the other hand the QCC values calculated with use of the pseudo potential for the central atoms provided much lower than the experimental ones. At the same time the QCC values of the central atoms calculated by B3LYP/3-21G* were well correlated with experimental values. The ZPE corrected complexation energies of the SbCI5L complexes do not upgrade the binding energies towards the experimental Gutmann's donor numbers. The donor-acceptor bonds for all complexes have a high degree of ionic character. The Wiberg bond order values determine of the detection of the metal-ligand bond orbitals with the exception of niobium complexes by NBO approach. The value of Wiberg bond order must be not lesser than 0.3. The donor-acceptor interactions of main-group elements such as Sb and Sn described in terms of the sp hybridization just as these interactions of transition metal elements mean sd hybridization.

Investigation of tin and antimony compounds using nqr, X-ray electron and quantum-chemical calculations // Tomsk State Pedagogical University Bulletin. 2000. Issue 9 (25). P. 9-11

The semiempirical PM3 method was applied for analysis of such experimental parameters as NQR frequencies, energy levels in X-ray electron and X-ray fluorescence spectra. The subjects of the study were complexes of tin and antimony. The strong correlation established between the differences in the energies in the inner energy levels of tin, antimony, chlorine atoms and the corresponding ClKa shifts. The obtained correlation dependencies can be used for the characterisation of the donor ability of ligands.

STUDY OF THE COORDINATION EFFECTS FOR SnCl4, SbCl5 AND TiCl4 COMPLEXES ON THE BASE OF AB INITIO CALCULATIONS // Tomsk State Pedagogical University Bulletin. 2002. Issue 2 (30). P. 10-17

In this paper ab initio HONDO calculations of SnCI4, SbCI5 and TiCI4 with H2S complexes have been per¬formed. All 35CI-NQR frequencies for above-men¬tioned nv-complexes are obtained by ab initio calcula¬tions. It was shown that ab initio calculations might be useful for the appropriate interpretation of experimen¬tal NQR frequencies. The optimized geometry of the complexes has been used to calculate the quadruple coupling constants, the ionization potentials, the MO composition and the orbit¬al energies for each of the compounds investigated. Our calculations have been pointed out that TiCI4, SnCI4 and SbCI5 complexes are somewhat stabilized. The most stable complex is SbCI5 that is in a good agreement with the experimental data. The stability of the complexes depends both on the stabilization of the occupied donor molecular levels and the vacant ac¬ceptor and donor levels.