Hydrogen diffraction from the (110) surface of silver
Abstract
The scattering of H2 and D2 molecules at thermal energies from the Ag(110) surface has been studied by means of nozzle-beam techniques. Diffraction peaks of comparable intensities are present along both the [001] and the [110] azimuthal directions, indicating a two-dimensional repulsive corrugation. The diffraction intensities were resolved over a wide range of incident angles and energies. The experimental H2 data are analysed theoretically to obtain information on the repulsive molecule–surface interaction potential. The calculations are performed (a) with the hard-corrugated-wall potential, (b) with a soft-corrugated-wall model and (c) performing close-coupling calculations for a flexible phenomenological potential. The best-fit interaction potential shows that the two-dimensional repulsive corrugation has a weak dependence on energy. A comparison is made between the H2–Ag(110) and He–Ag(110) potentials and the H2 and He diffraction from the Ag(111) and Cu(110) surfaces.