Affiliations: [a] Laboratoire de Physique et Chimie d'Interfaces, Département de Physique, Faculté des Sciences de Monastir, Avenue de l'Environnement 5019, Monastir, Tunisia | [b] Physics Department, Faculty of Sciences, King Khalid University, P.O. Box 9004, Abha, Saudi Arabia
Abstract: The potential energy curves of the electronic states of 2Σg,u+, 2Πg,u and 2Δg,u symmetries of the K2+ molecular ionic system dissociating into K (4s, 4p, 5s, 3d, 5p, 4d and 6s) + K+, have been calculated. The computation was performed using an ab initio approach, where a non-empirical pseudopotential for the K+ core has been involved and a core-core and core valence correlation corrections have been added. The spectroscopic constants have been derived and compared with the available theoretical and experimental works. A good agreement has been obtained for the ground and the first excited states. However, a clear disagreement between this study and the model potential work of Magnier and Aubert-Frécon [J. Quant. Spect. Rad. Trans. 78, 2003] has been observed for several excited states. They found that the 52Σu+, 62Σg+, 62Σu+, 72Σg+, 72Σu+, 42Πg and 22Δu states are repulsive, although they are attractive with potential well depths of 10, 100 and 1000 cm−1 in our study. Furthermore, the atomic polarizabilities have been predicted from a vibrational spacing analysis based on the WKB approximation applied on the potential energy at long-range distances. These polarizabilities have been used to reproduce the long range potential interaction for some electronic states.
