The scattering of ions from a clean solid surface in the 1 to 10 eV range

Abstract We have proposed a surface model which consists of partially screened spherical caps oscillating in a direction normal to the undisturbed surface to correlate measurements of the trapping probability of sodium and potassium ions on clean (110) tungsten surfaces at energies of 1 to 15 eV and incidence of 10° to 70° from the normal to the surface. The trapping probability may be represented as a relatively simple function of angle, mass ratio, surface temperature and beam energy to ionization potential ratio, with good agreement with experimental data. The model depends on some assumptions about elevation and azimuthal screening of lattice sites which cannot fully be justified from first principles. Further analysis of the data, particularly with respect to scattered particle distribution and additional data for the scattering of lithium and cesium might help refine those assumptions.