Applying ab initio Calculations to Theoretically Investigate the
Electronic Structure of the Calcium Sulfide Molecule CaS
Abstract
Using the graphical user interface GABEDIT and the computational chemistry software MOLPRO, the ab initio
calculation method has been applied to explore 25 low-lying singlet and triplet electronic states, including the X1Σ+
ground state, of the calcium sulfide molecule CaS in the 2s+1Λ± representation. The multi-reference configuration
interaction with Davidson correction (MRCI+Q) and the complete active space self-consistent field (CASSCF)
calculations were performed to obtain the potential energy curves in terms of the internuclear distance R. The
permanent dipole moments μe of these low-lying electronic states of CaS have been investigated, in addition to the
corresponding spectroscopic constants (including the electronic energy with respect to the ground state Te, the
equilibrium internuclear distance Re, the harmonic vibrational frequency ωe, the rotational constant Be, and the
equilibrium dissociation energy De). In the present work, 19 new singlet and triplet CaS electronic states were
investigated for the first time. In addition, it is noticeable that the current results and those already available in
literature are in good agreement.
Journal/Conference Information
Modern Applied Science,DOI: 10.5539/mas.v13n1p1, Volume: 13, Issue: 1, Pages Range: 1-9,