EXAFS and XANES Studies of Superionic Cu_2−xSe

Abstract

The measurement of the EXAFS spectrum of superionic Cu_1.8Se has been carefully carried out. The local structures around the Cu and Se atoms are determined. The Cu atoms around the tetrahedral site of Se atoms are detected but those around the octahedral site are not found. The XANES spectrum of Cu_1.8Se was also measured and compared with that of Cu₂Se.