GENERALIZED HEITLER-LONDON THEORY WITH EXCHANGE ENERGY BY THE SURFACEINTEGRAL METHOD - AN APPLICATION TO THE ALKALI-METAL DIMER CATIONS

The generalized Heitler-London theory is used to calculate the lowest gerade and ungerade potential energy curves of the alkali metal dimer cations Li-2(+), Na-2(+), K-2(+), Rb-2(+) and Cs-1(+). The exchange en ergy is calculated with the surface integral method and the second ord er polarization energy by a damped induction series. The results depen d only on the properties of the atomic constituents and thus the poten tials of all these systems are generated by the same formula without a ny adjustable parameters. For Li-2(+) and Na-2(+) die results agree we ll with accurate CI calculations. The observed discrepancies for Rb-2( +) and Cs-2(+) with previous estimates are discussed.