ION-SCATTERING STUDIES OF MODIFIED METAL-SURFACES

The technique of ion backscattering and channeling provides valuable information about the structure of solid surfaces, both clean and as modified by adsorbed atoms. Analysis of the backscattering data is based on the concepts of shadowing and blocking. Because the theory of Rutherford scattering is well understood, it is possible, using comparisons between experiment and computer simulations for model structures, to extract information about the geometry and dynamics of atoms on solid surfaces. Studies of the structure of clean W(110) and Nb(110) surfaces, and the modification of these surfaces with H adsorption/absorption will be presented. Ion scattering also provides structural information about solid-solid interfaces. Results for Pd deposited on Al(111), and for Ni on W(110) will be discussed.