A vibrational level spacing analysis of the LiK+ lowest electronic states: Long-range behavior and evaluation of Li and K polarizabilities

A vibrational level spacing analysis of the lowest electronic states of the LiK+ ionic molecule dissociating into Li(2s, 2p, 3s, 3p, 3d, 4s and 4p) + K+ and Li+ + K(4s, 4p, 5s, 3d, 5p, 4d, 6s) has been performed using the usual WKB semiclassical approximation. Accurate long-range potentials have been determined and allowing for the determination of all vibrational levels near the dissociation limit, the Li and K atomic polarizabilities, the number of trapped vibrational levels, and the vibrational turning points. The extracted polarizabilities for the ground levels of Li and K atoms have been compared with the available theoretical and experimental values. A very good agreement has been shown for them. The obtained atomic polarizabilites have been used to reproduce the long-range potential energy curves showing the good agreement between the ab initio calculated and the analytical potentials. A systematic generation of the missed Numerov vibrational levels and their turning points near the dissociation limit was done for all the LiK+ electronic states.