Rainbow Scattering of Inert Gas Atoms on Aluminum and Silver Crystal Surfaces

Particle trajectories are calculated to study the rainbow scattering and the focusing of Ar atoms on the Al(111) and Ag(111) crystal surfaces and Ne, Ar, and Kr atoms on the Al(001) crystalsurface. The rainbow-scattering-induced features in spectra are used to determine the thermal vibration amplitudes of atoms for the Al(111) and Ag(111) targets. These data agree with the data of independent measurements. The dependence of the position of a rainbow peak on the initial energy of atomsis used to find the atom-surface interaction potentials in the energy range of 0.3-70 eV for the case Ar-Ag and 3-45 eV for other cases. The values and the functional dependences of the potentials on the internuclear distance differ strongly from the well-known pair potential models. This difference is associated with the interaction of a projectile atom with the conduction electrons in a metal.