HIGH-RESOLUTION AG L-3-XANES STUDIES OF AUAG ALLOYS USING THE ELECTRON YIELD OF A NARROW AUGER CHANNEL

The Ag L-3-XANES for Ag metal and a series of Au-Ag alloys, AuAg3, AuA g and Au3Ag have been obtained by monitoring the intensity of the Ag L -3-M4,5M4,5 Auger electrons with high energy resolution. The selected (1)G(4) final state has a much longer lifetime than the L-3 core hole which results in a reduced lifetime broadening of the partial yield sp ectra. Subtle features which are predicted by theory and barely visibl e in total yield spectra are clearly resolved here. The experiment con firms the earlier conventional XANES observation that Ag gains d charg e upon alloying with Au. Full-scale multiple scattering calculations h ave been carried out for the Ag L-3-XANES of Ag and AuAg. The results are discussed in the context of electron charge redistribution and uno ccupied densities of states.