OBSERVATIONS ON THE D-BAND WIDTH OF AU-AG AND AU-CU ALLOYS

The d-band widths of a series of Au-Ag and Au-Cu alloys have been studied with photoemission spectroscopy. The main concern is whether or not the Au d band width is maintained in these alloys. It is found that in concentrate alloys (> 50% atomic Au), the alloy d-band width narrows little in both Ag and Cu alloys relative to that of pure Au. At 25% (and less) atomic Au concentration however, the d band widths of the Au alloys in the two hosts are significantly different. While the d-band width of Cu3Au (ordered and disordered) remains the same as that of the pure Au, the d-band width of Ag3Au (disordered) narrows by approximately 1eV. The implication of this observation is discussed in terms of dilution and chemical effects.