THEORETICAL SPECTROSCOPIC PARAMETERS OF THE ALKALI MONOFLUORIDES LIF, NAF AND KF

Multireference configuration interaction and second-order perturbation theory are used to determine accurate spectroscopic parameters for the ground state of the alkali monofluorides from LiF to KF. Systematic saturation of the spdf subspaces of the atomic basis sets for the electron affinity of fluorine and the ionization potential of the metals have been shown to be more efficient than for the approximate dissociation energies in the molecule. The calculated rotational and vibrational constants and transitions for the three systems show excellent agreement with the experimental data.