MOLECULAR-STRUCTURES AND VIBRATIONAL-SPECTRA OF SELENOFORMALDEHYDE AND ITS THIOANALOGS AND OXO-ANALOGS BY ABINITIO POST-HARTREE-FOCK STUDY

Ab initio post-Hartree-Fock calculations were carried out on H2CSe, H2CS and H2CO. Equilibrium geometries, harmonic frequencies and integrated intensities were calculated at the MP2 level using valence double-zeta (d, p) basis set on H, C, O and S, and Huzinaga valence triple-zeta (d) basis set on selenium, respectively. Predicted geometrical parameters, dipole moments and vibrational frequencies compare well with the available experimental data. The harmonic vibrational frequencies nu-1 and nu-5 calculated for selenoformaldehyde which are still experimentally elusive may be helpful in further experimental studies on this species.