AB-INITIO STUDY OF HIGH-SPIN CHEMICAL BONDING OF MCO AND MCS (M=Y-MO)

The high-spin electronic ground states of MCO and MCS molecules, where M = Y, Zr, Nb, Mo, were calculated with ab initio method. Relativisti c small-core Hartree-Fock pseudopotentials were used for the metal ato ms, and flexible basis sets were used for all the atoms. Single and do uble configuration interactions and perturbation calculations were don e. The equilibrium geometries, vibrational frequencies, bond energies, dipole moments, electron affinities, and ionization potentials are re ported. The equilibrium characteristics of the anions and cations of t hose molecules were also given. The (Y-Mo)CO and (Y-Mo)CS molecules sh owed similar properties as the (Sc-Cr)CO and (Sc-Cr)CS molecules.