Ab initiostudy of one- and two-electron transfer processes in collisions ofNe2+with He at low to intermediate energies

Abstract

One- and two-electron-transfer processes resulting from ${\mathrm{Ne}}^{2+}$ collisions with He are studied, based on a molecular-orbital close-coupling method within the semiclassical representation for the collision energy range of 10 eV/u--10 keV/u. One-electron processes are considered from ground state ${\mathrm{Ne}}^{2+}{(}^{3}P)$ as well as from the metastable ions ${\mathrm{Ne}}^{2+}{(}^{1}D)$ and ${\mathrm{Ne}}^{2+}{(}^{1}S).$ Two-electron processes are considered only for metastable ${\mathrm{Ne}}^{2+}{(}^{1}D)$ and ${\mathrm{Ne}}^{2+}{(}^{1}S)$ collisions. Previous electron-transfer experimental cross sections show a weak energy dependence, while the present theoretical results for the ground-state ion impact have a pronounced energy dependence, decreasing with decreasing collision energy. However, the theoretical cross sections for the metastable ions are found to be weakly dependent on the collision energy. If the ion beams used in the experiments are assumed to have contained some fraction of metastable ions, then the present results appear to be consistent with the measurements.