Doppler-free spectroscopy of KLi

Abstract

The B 1∏–X 1∑+ band system of the 39K7Li molecule was investigated by Doppler-free polarization spectroscopy in a heat-pipe oven. Precise molecular constants for levels v=0–3 in the ground X 1∑+ state and levels v=0–2 in the excited B 1∏ state were determined. The e-parity components in all three vibrational levels of the B state were found to be subject to rotational perturbations, assigned to interaction with the C 1∑+ state. The deperturbation analysis provided preliminary constants of the perturbing C state and values of the coupling matrix elements.