Diffraction of H2 from metal surfaces

Abstract

Diffraction of molecular hydrogen is a very sensitive technique to characterize the potential energy surface (PES) for hydrogen dissociative chemisorption. In this chapter we summarize recent H2 diffraction experiments and calculations based on ab initio determined six-dimensional PESs performed on several single-crystal metal surfaces, ranging from non-reactive to very reactive ones, at incident energies between 20 and 200 meV. The general trends observed in experiment are discussed, as well as the validity of the approximations usually employed in the calculations. It is shown that an analysis of both H2 elastic and rotationally inelastic diffraction intensities as a function of incident energy provides a very sensitive way to test the quality of ab initio determined six-dimensional PESs. © Springer-Verlag Berlin Heidelberg 2013.