Theoretical study of potential energy curves, spectroscopic constants, and radiative lifetimes of low-lying states in an SeO molecule

The low-lying potential energy curves of the SeO molecule are computed by means of an ab initio multireference configuration interaction technique, taking into account relativistic (scalar plus spin—orbit coupling) effects. The spectroscopic constants of Ω states for X3Σ−, a1Δ, b1Σ+, A3Π, A'3Δ, and A'' 3Σ+ states are obtained, and they are in good accordance with available experimental values. The Franck—Condon factors and transition dipole moments to the ground state are computed, and the natural radiative lifetimes of low-lying Ω states are theoretically obtained. Comparisons of the natural lifetimes of Ω states with previous experimental results and those of isovalent TeO molecule are made.