MOLECULE-SCATTERING FROM SOLID-SURFACES - ORIENTATION AND SURFACE CORRUGATION EFFECTS

Various effects connected with orientation and surface corrugation in molecule scattering from solid surfaces are investigated by means of c lassical trajectories simulations for H-2 impinging on Pd(110). Primar y excitation of the projectiles is modeled according to the situation in molecular beam experiments, where vibrational levels are occupied u p to upsilon = 10 and more. Elastic interactions are mediated by an ex tended EAM potential, while inelastic effects an ignored. A correlatio n is found between the molecular orientation at the time of impact and the relative position of collisionally dissociated fragments. For gra zing incidence along surface semichannels, rotational excitation is fo und with angular momentum vector parallel to the direction of flight ( propeller mode). The survival probability shows no scaling with E-perp endicular to for varying energies and angles of incidence.