SCATTERING OF FAST N-2, N-2(+) AND N-2(2+) FROM AL(111) UNDER GLANCING ANGLES OF INCIDENCE

We have scattered 1-4 keV N-2, N-2(+) and N-2(2+) beams from an Al(111) surface under glancing angles of incidence of 1-4 degrees. The scattered neutral particle energy/atom distributions are insensitive to the initial charge state of the beam. We conclude that dissociation of both N-2(+) and N-2(2+) proceeds via a mechanism which is unrelated to direct charge transfer to unbound or predissociative states of N-2. A dissociative scattering mechanism involving multiple electronic transitions provides a possible explanation both for the dissociative scattering of neutral N-2 and the observation of two sharp features in the energy/atom distributions.