Elastic and inelastic atomic beam scattering from Ni(115)

Scattered angular intensities of the elastic diffraction of nearly monoenergetic helium beam from a Ni(115) crystalline surface in the [552] direction at a variety of incident energies and polar angles was measured. A method is developed of mapping the corrugation parameters from the hard-wall diffraction model, which fit the experimental data, to the corrugation parameters in the soft wall (Morse potential) model. The experimental data was fit by the soft wall model with only minor adjustments of the mapped corrugation parameters for well depth of 8.0 MeV and a steepness parameter of 2.2 reciprocal angstroms. The inelastic scattering of argon at an incident angle of 300 for a variety of incident energies and surface temperatures was measured both as a function of reflected angle and as a function of time for narrow incident pulse shapes at the angle corresponding to the backscattered rainbow maximum in the [552] direction, and at the specular angle in the [110] direction. The angular scans show the intensity is peaked at a backscattered rainbow angle in the [552] direction, and is peaked at the specular angle in the [110] direction. The time-of-flight measurements show that a linear relationship between the reflected energy and the incident energy and between the reflected energy and the surface temperature is obeyed