Dissociative scattering of molecular beams from crystal surfaces: H2, N2 and NO from Cu(111) studied by translational spectroscopy

Abstract

We have measured the kinetic energy release and final molecular axis orientation in dissociative molecular scattering of neutral H₂, N₂ and NO from Cu(111) under glancing incidence conditions. The final orientation distributions of H₂ and N₂ and NO are completely different. The results are insensitive to the crystal azimuth and thus to the geometrical corrugation of the crystal surface. We propose that dissociative scattering occurs via repeated transitions between potential-energy surfaces, and provides classical simulations of this process in the limits of strong and weak coupling. The influence on the results of both the strength of the coupling and the topography of the participating states is discussed.