Multiple Scattering Approach to Pd L 3 -Edge X-Ray Absorption near Edge Structure Spectra for Small Pd Clusters with Hydrogen Adsorption and Absorption

Recent studies on Pd L 3 -edge X-ray absorption near edge structure (XANES) spectra for pure small Pd clusters show that the spectra are strongly influenced by hydrogen adsorption and absorption. In this paper, the full multiple scattering method is applied to study the difference in measured spectra. The calculated XANES spectra are not so sensitive to the detailed positions and the electronic structures of the interacting hydrogen atoms, however they are sensitive to the induced structural and electronic state change in the host small Pd clusters. The size effect on the peak at ∼7 eV from the edge is well explained by the induced lattice expansion after hydrogen absorption.