The field my scientific interests is study of internal properties of polyatomic molecules on the base of information from high resolution spectra.

At the present time on the base of the 'expanded' local mode approach and general isotopic substitution theory we obtain sets of simple analytical relations between spectroscopic parameters (harmonic frequencies, anharmonic coefficients, ro-vibrational parameters, different kinds of Fermi and Coriolis-type interaction parameters) of polyatomic molecules. All of them are expressed as simple functions of spectroscopic parameters of the mother molecule. On the base of operator perturbation theory and the symmetry properties, we derive general formulae for the determination of the spectroscopic parameters in the form of functions of structural parameters and parameters of the intramolecular potential function.

The main results of research:

1) The 'expanded' local mode approach and the general isotopic substitution theory were used to estimate the relations between spectroscopic parameters of the T_d symmetric isotopic species, XY₄, on the one hand, and with different isotopologues, on the other hand. Test calculations were made for methane molecule.

2) The 'expanded' local mode approach and symmetric properties were derived for six atomic Х₂Y₄ type molecules of D_2h symmetry. Test calculations were made for C₂H₄ molecule.

3) High resolution spectra of C₂D₄, GeH₄, SiH₄, CH₃D were investigated.