Electronic Structure of the Cesium Oxide Molecule CsO

Abstract

Adiabatic potential energy curves of 12 doublet and quartet lowest spinless electronic states of the molecule CsO have been investigated via ab initio CASSCF and MRCI (doublet and quartet excitations with Davidson correction) calculations. The spectroscopic constants such as vibrational harmonic frequency ωe, the internuclear distance at equilibrium Re, the rotational constant Be, and the electronic transition energy Te of the ground and the excited electronic states have been calculated by fitting the energy values around the equilibrium position to a polynomial in terms of the internuclear distance. The comparison of these values to those available in the literature shows a good agreement.

Electronic and Vibrational Spectroscopy of CsS

“…To understand the phenomena taking place during these reactions and in plasma, one needs a full characterization of the involved atomic and molecular species. Since alkali-metal monoxides are commonly found in many high-temperature systems, they have been the subject of many studies, both experimental and theoretical. − However, their sulfur isovalent analogues, i.e., alkali-metal monosulfides (MS), were investigated, , but not to the same extent; consequently, there is a lack of information on these molecules. For instance, spectroscopic data on CsS, of interest in the present study, are limited to the determination of the nature of its lowest lying electronic states by Partridge et al and by Lee and Wright .…”