One-Electron Pseudopotential Investigation of CsAr van der Waals System Including the Spin−Orbit Interaction

Abstract

The potential energy curves of the ground state and many excited states of the CsAr van der Waals system have been determined using [Cs(+)] and [Ar] core pseudopotentials and by considering core polarization operators on both atoms. This has permitted to reduce the number of active electrons of the CsAr system to only one electron, i.e., the valence electron, which led to use of large basis sets for Cs and Ar atoms. In this context, the potential energy curves of the ground state and many excited states are performed at the self consistent field (SCF) level. Spin-orbit interaction is also considered within a semiempirical scheme for the states dissociating into Cs(6p) and Cs(5d). The core-core interactions for Cs(+)Ar is included using the coupled cluster simple and double excitation (CCSD) accurate potential of Hickling et al. (Hickling, H.; Viehland, L.; Shepherd, D.; Soldan, P.; Lee, E.; Wright, T. Phys. Chem. Chem. Phys. 2004, 6, 4233). In addition, the spectroscopic constants of these states are derived and compared with the available theoretical and experimental works. Such comparison has shown a very good agreement for the ground and the first excited states. However, the spectroscopic data for the higher excited states are presented for the first time.

Electronic, spectra, and spin orbit interaction for FrAr van der Waals system

“…It was shown previously18, 27, 41 that the SO interaction is not negligible for alkali metal‐argon dimers, MAr, except when the involved alkali atom are Li and Na. In fact, this effect starts to be significant from M = K and increases with the mass of the alkali atom.…”

“…This exercise provided a convincing validation of the computational model. Recently, Dhiflaoui and Berriche41 studied CsAr using the same technique. They determined the potential energy curves and the spectroscopic constants for the ground and many excited states.…”

Electronic Absorption Spectra of the RbAr Van der Waals Complex

“…The three terms are well developed in our previous works [22][23][24]. The Rb + Ar potential interactions are fitted to a Tang …”

“…Therefore, accurate data for the upper and lower electronic states of alkali metal-rare gas pairs are needed to evaluate the scaling possibilities for alkali metal rare gas dimer lasers. The alkali Rare gas diatomic systems have recently received considerable attention both experimentally [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] and theoretically [18][19][20][21][22][23][24]. In fact, they are considered as model systems for van der Waals molecules.…”

“…More recently, we have studied the CsAr system [22][23] using one-electron pseudopotential. Our spectroscopic constants have been derived and compared to theoretical and experimental ones, which have validated the used approach.…”