X-RAY-ABSORPTION NEAR-EDGE STRUCTURE (XANES) STUDIES OF AU0.5AG0.5 - IMPLICATION FOR CHARGE REDISTRIBUTION AT BOTH AU AND AG SITES UPON ALLOYING

L-edge x-ray absorption near edge structure (XANES) has been used to s tudy electronic structure of the titled alloy. It is found that (a) re lative to pure Au, the alloy Au L2,3 edge XANES exhibits an increase i n absorption coefficient just above the edge, indicating d-charge depl etion at the Au site; (b) relative to pure Ag, the intensity of the al loy Ag L2,3-edge ''whiteline'' of the alloy decreases indicating d-cha rge gain at the Ag site; (c) these observations are accompanied by an increase in the Ag L1-edge ''whiteline'' intensity, a sign for the dep letion of p charge. These results are discussed in terms of a charge c ompensation model.