M3,2-Edge X-Ray Absorption Near Edge Structure of 5d Metals

We report M 3,2 edge XANES measurements for a series of 5d metals, Hf, Ta, W, Re, Ir, Pt and Au using a total electron yield technique. It was found that the M 3,2 XANES for most 5d metals exhibit intense resonances at the threshold (whitelines). The area under the whiteline correlates with the unoccupied densities of d states of the metal. The M 3,2 XANES features and their systematics are comparable to their L 3,2 counterparts. These results clearly suggest that M 3,2 edge XANES can be used as an alternative probe to the conventional L 3,2 -edge XANES for the unoccupied densities of d states of the 5d metals and their compounds.