ENERGY-LOSS SPECTRA OF H-SURFACES( AND H(0) SCATTERED OFF METAL)

We recorded energy spectra after scattering of H+ and H-0 off Ni surfa ces. The incident energy range was 0,5-5 keV, we used 5-degrees incide nt angle and a scattering angle of 10-degrees. Hence nearly all partic les probe only the surface region and do not penetrate into the bulk. To account for the resulting spectra we modified our previously succes sfully applied model of the He/metal-surface interaction and adapted i t to the H/metal-surface system. The main difference is the number of charge states involved. In the He case there are two ''active'' charge states (He+, He-0) for the energy region under consideration, whereas for H we have to deal with three charge states (H+, H-0 and H-).