Structure analysis of Au-containing cuprate of Au1+xBa2Ca2Cu3−xO9 (Au-1223)

Single crystals of Au1+xBa2Ca2Cu3-xO9 (Au-1223) were grown at 6 GPa and 1325 C. This phase is the third member of the Au-containing cuprate family of AuBa2Can-1CunO2n+3 and shows a weak signal of superconductivity. The crystal structure was refined to R1 (I > 2s(I))=0.0188 and wR2=0.0485 with F2 data. The Au-1223 phase crystallizes in the space group Pmmm (no. 47), a=3.8119(1) A, b=3.8556(1) A, c=15.4431(5) A, Z=1. Partial substitution of Au for Cu in the CuO2 planes was revealed. The Au incorporation to the conduction layers may be a reason for the suppression of superconductivity in Au-1223. 12 refs.