Studies of valence of selected rare earth silicides determined using Si K and Pd/Rh L2,3 XANES and LAPW numerical studies

The observed changes indicate that despite possessing a formal inter-metallic character, the chemical bond between the R-Si and R-Pd interactions are different. The variation and the direction of the chemical shift of the Si K edge suggests a weak ionic character of the R-Si bonds, in agreement with the localized character of the 4f electrons. In turn, the changes of the Pd/Rh edge are consistent with a metallic band that is affected by its long range chemical environment.