Surface green function matching approach to the surface dynamics of ionic crystals: II. Theoretical analysis of the inelastic scattering of He from NaF(001) in the eikonal approximation

A theoretical analysis of recent scattering time of flight (TOF) data for NaF(001)/He is done by means of a new version of the eikonal approximation to the inelastic processes, which allows for the use of atom-surface potentials obtained by summing over two-body potentials. A Morse potential for He-ion interactions is adopted in the present work. A good agreement between theory and experiment is found with the present scheme.     

Theory of one-phonon scattering of atoms from metal surfaces: Application to He/Ag(111)

We present explicit expressions for one-phonon scattering of atoms from metal surfaces, within the distorted wave Born approximation by including Van der Waals forces. A comparison is made with the recent high-resolution time of flight spectra for He/Ag(1 1 1). We explain in quantitative terms the position and the intensity of the peaks due to scattering from the Rayleigh wave of silver. Also the bulk phonons contribute to the spectra, but the calculated intensities underestimate the data.     

Effect of inelastic transitions on the line shape of surface resonances

We show that the inelastic resonant processes discussed by Cantini and Tatarek affect the line shape of elastic resonances. This effect is not included in the Debye-Waller correction to the repulsive matrix elements, as used by Hutchison and others, and may explain the discrepancy between the line strengths predicted by Hutchison's formulae and those observed by Cantini et al.