Scattering of hydrogen molecules from a reactive surface: Strong off-specular and rotationally inelastic diffraction

Six-dimensional quantum dynamical calculations of the scattering of H2 from a Pd (100) surface using a potential energy surface derived from density functional theory calculations are presented. Due to the corrugation and anisotropy of the PES strong off-specular and rotationally inelastic diffraction is found. The dependence of the diffraction intensities on the incident kinetic energy is closely examined. In particular we focus on the quantum oscillations for normal and off-normal incidence.