Semi-empirical calculations on the hydrogen molecule by a parameterization obtained from helium-like atomic systems

Semiempirical redn. factors calibrated on an empirical linear relationship between the square root of ground-state electronic energy and at. no. in the He isoelectronic series can be used to allow for interelectronic repulsion in calcns. of electronic energies of mol. systems. Depending on the type of wave function used, redn. factors can vary with mol. geometry. Results of such calcns. on H2 and He22+ are compared with qunatities derived from accurate Kolos-Roothaan potential curves (1961).