Аннотация:The geometrical structures, charge distributions, dipole moments, frequencies of normal vibrations, NMR spectra, and total energies of the chemical bonds for the rhenium alkoxo derivatives Re2O3(OMe)6, Re4O6(OMe)12, and ReMoO2(OMe)7 were calculated by the DFT-B3LYP and Hartree-Fock ab initio methods based on the effective core potential theory (LANL2DZ approximation) and the semiempirical PM3(tm) method. Two optimized structures of Re2O3(OMe)6 with close energies were found to substantially differ in geometry, 1H, 13C, and 17O NMR spectra, and dipole moment. Various characteristics of the electronic structures and the trans-effect of the ligands in the compounds under consideration were discussed.