The density of unoccupied p states of silver, palladium, and palladium silicide has been measured for the first time with high resolution by x-ray absorption at the $M_{\mathrm{I}\mathrm{V},\mathrm{V}}$ edges. Our results show that the $M_{\mathrm{I}\mathrm{V},\mathrm{V}}$-edge spectra yield information for 4d metals similar to that provided by K and $L_{\mathrm{I}}$ edge measurement on 3d metals. The densities of states are in agreement with theoretical predictions both in regard to energy and relative intensity. Changes in the palladium $M_{\mathrm{I}\mathrm{V},\mathrm{V}}$ spectra on silicide formation give the first direct evidence of the role of Pd 5p states in compound formation.

• Received 27 November 1989

DOI:https://doi.org/10.1103/PhysRevB.41.3862