Theory of inelastic atom-surface scattering: A three-dimensional treatment

Inelastic scattering of atoms by solid surfaces is treated within the first order distorted wave Born approximation. The solid is treated as a semi-infinite elastic continuum and the phonon excitations of this system are properly taken into account, including the Rayleigh waves. No restriction concerning the scattering angles (in and out) are made. In particular momentum transfers parallel to the surface are taken into account. The contribution of all these effects to the sticking coefficient are considered in detail. It turns out, that the Rayleigh phonons contribute about 25% to the local density of phonon states at the surface and roughly 50% to the sticking coefficient. The three dimensional motion of the scattered particle (in particular the transfer of parallel momentum) increases the sticking coefficient by a factor of about three as compared to one dimensional treatments.