Dynamical resonant electron capture in atom surface collisions:H−formation in H-Al(111) collisions

The formation of ${\mathrm{H}}^{\mathrm{-}}$ ion by grazing-angle collisions of hydrogen on an Al(111) surface is investigated with the newly developed coupled angular mode method. The capture process involves a dynamical resonant process induced by the collision velocity. All the resonance properties of the ${\mathrm{H}}^{\mathrm{-}}$ level in front of an Al(111) surface are determined: position, width, and angular distribution of ejected electrons. The results are shown to account for the recent observations on ${\mathrm{H}}^{\mathrm{-}}$ formation by Wyputta, Zimny, and Winter.