Ground and excited states of Ne2 and Ne2+. I. Potential curves with and without spin-orbit coupling

Abstract

Ab initio configuration-interaction calculations on ground-state Ne2, the excited Σu,g+1,3 and 1,3Πu,g states of Ne2 formed from Ne(3s; 1,3P) and Ne(1S), and the Σu,g+2 and 2Πu,g states of Ne2+ have been carried out. The dissociation energies of the Σu+1,3 excited states of Ne2 were found to be considerably smaller than that of the corresponding molecular ion. Potential maxima were found in the attractive interactions of the excited Ne2 molecule. A semiempirical model, based on the observed atomic splittings, is given for treatment of spin-orbit coupling effects. The adiabatic potential curves resulting from diagonalization of the spin-orbit interaction were found essential to the understanding of spectroscopic observations. Estimates of the long-range dispersion interactions are also presented.