Valence of Au in AuTe2 and AuSe studied by x-ray absorption spectroscopy

Article abstract of DOI:10.1016/0038-1098(94)90343-3

The gold compounds AuTe₂ and AuSe contain Au atoms in two different chemical surroundings. In the literature these different coordinations have been associated with a difference in valency of the Au atoms. In this paper the occupation of the 5d shell in AuSe and AuTe₂ is deduced from a study of the 4f → 5d X-ray absorption edge. A comparison is made with the absorption edges of Au, AuCl and AuCl₃. The results show that only AuCl₃ has Au atoms in a valence state of III, and that the Au atoms in AuTe₂ and AuSe are all in the same monovalent state I, independent of their chemical environment.