Low energy electron collisions with He 2+ molecules

Abstract

The R-matrix method is used in an ab initio study of low energy elastic scattering by He 2 + molecular ions. SCF and correlated CI wavefunctions have been used in a two state approximation, which retains the lowest two states, 2∑ u + and 2∑ g +, of the He 2 + molecular ion in the scattering basis. Cross section calculations have been performed at two fixed internuclear separations, 1.8 and 2.0625 a 0. At the equilibrium bond separation we have detected and fitted the lowest lying n pσ 3Σ u + resonances in the 3Σ + u scattering symmetry. In addition, bound state calculations have also been carried out for the He 2 (1 σ g +1 σ u2s a 3 Σ u +) state at these two internuclear separations and are seen to compare favorably with MCSCF and SOCI results.