RESONANT INELASTIC-SCATTERING OF ATOMS FROM SURFACES

In this paper, we present a new formulation of inelastic scattering of atoms from surfaces within the close-coupling formalism using a classical description of the surface motion. In this formulation, the diffraction channels exhibit not only moving thresholds but are also shifted (or dressed) by amounts of energy equal to the excitations of the active mode, taking into account all the creation and annihilation processes accesible by energy conservation. These inelastic diffraction channels can be arranged in blocks (Floquet blocks) differing by one quantum. When a continuum model for the surface and a soft potential including an attractive well is considered for the interaction, good agreement with the thermal attenuation of the specular and diffracted intensities and resonance line shapes is obtained compared to the experimental ones. Within the single-phonon approximation, multiphonon contributions of the same excited mode are also analyzed for non-resonant, resonant and critical scatterings. Application to the weak corrugated metal surfaces Cu(110) and Cu(113) is presented and discussed.