The interaction of tin with cerium oxide thin film and cerium oxide nanosized powder was studied using XPS and resonant photoelectron spectroscopy (RPES) in the Ce 4d-4f photoabsorption region. A strong tin-ceria interaction led to partial Ce 4+ → Ce 3+ transition and Sn + ion formation. A corresponding increase of the Ce 4f state occupancy was observed as a giant 4f resonance enhancement. In the case of powder catalyst a strong CeO 2 -Sn interaction lead to formation of Ce-Sn-O mixed oxide system characterized by Ce 3+ ion concentration enhancement and increase of Ce 4f occupation. It explains generally higher catalytic activity of the Ce-Sn-O mixed oxide catalysts when comparing with the individual oxides.

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He beam scattering measurements of the erosion of the InSb(110) surface by low-energy Ar+ bombardment are reported. Layer-by-layer erosion is observed for surface temperatures above 510 K and is found to proceed by nucleation of vacancy islands, island growth, and coalescence. The average island distance is measured at different stages of the erosion process and it is found to evolve in good agreement with the rate equations derived from models of island growth by atomic deposition. A general increase of the average terrace width is also observed with increasing number of removed layers. The activation barrier for intralayer diffusion of InSb dimer vacancies is found to be Ed=1.14±0.06 eV

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