Effect of isotopic substitution on the effective dipole moment parameters in case of XY$_{2}$/XYZ type molecules

The dependence of the dipole characteristics on the isotopic substitution were discussed in the present work. On the bases of operator perturbation theory and group theory analytical relations for six effective dipole moment parameters (${}^{a_i}\mu_1$, ${}^{a_i}\mu_4$, ${}^{a_i}\mu_5$, ${}^{a_i}\mu_9$, ${}^{a_i}\mu_{12}$, and ${}^{a_i}\mu_{14}$) were obtained for the first time in case of asymmetric substitution XYZ $\leftarrow$ XY$_2$ . Relations which connect equilibrium dipole moment and first derivatives of the dipole moment of “mother” molecule with corresponding parameters of isotopic substituted species were derived for the first time. The quantitative calculation of the effective dipole moment parameters for ${}^{32}$S${}^{16}$O$_{2}{}$, ${}^{34}$S$^{16}$O$_{2}$, ${}^{32}$S$^{18}$O$_{2}$ and ${}^{32}$S${}^{16}$O${}^{18}$O molecules was performed.