Inelastic surface scattering of non-penetrating particles

This paper is an extension of the authors' earlier work to include a treatment of onephonon inelastic scattering of particles which do not penetrate appreciably into the crystal. A full quantum-mechanical treatment of the lattice vibrations is used throughout, and the results are not restricted to small scattered intensities. Calculations are presented for the scattering of helium atoms by a simplified model of the crystal surface.