Structure analysis of Au-containing cuprate of Au 1+ xBa 2Ca 2Cu 3− xO 9 (Au-1223)

Abstract

Single crystals of Au 1+ x Ba 2Ca 2Cu 3− x O 9 (Au-1223) were grown at 6 GPa and 1325 °C. This phase is the third member of the Au-containing cuprate family of AuBa 2Ca n−1 Cu n O 2 n+3 and shows a weak signal of superconductivity. The crystal structure was refined to R1 ( I>2 σ( I))=0.0188 and wR2=0.0485 with F 2 data. The Au-1223 phase crystallizes in the space group Pmmm (no. 47), a=3.8119(1) Å, b=3.8556(1) Å, c=15.4431(5) Å, Z=1. Partial substitution of Au for Cu in the CuO 2 planes was revealed. The Au incorporation to the conduction layers may be a reason for the suppression of superconductivity in Au-1223.