A LIGAND-FIELD APPROACH FOR THE LOW-LYING STATES OF CA, SR AND BA MONOHALIDES

The ligand field approach proposed by Rice, Martin and Field (J. Chem. Phys. 82 (1985) 5023) to describe the low-lying states of calcium monohalides has been extended to strontium and barium monohalides. Molecular wavefunctions are described in terms of model potential functions for alkaline earth ions. Transition energies, permanent and transition dipole moments have been evaluated. The three lowest excited states of each molecule are seen to be correctly represented in this way, the better agreement with experiment being displayed for barium compounds.