Refinement by the rietveld method and extended X-ray absorption fine structure of a 1,2,3-type ceramic oxide containing cobalt instead of copper

Abstract

The local structured around cobalt and yttrium ions in a 1,2,3-type ceramic oxide containing cobalt instead of copper, YBa_1.5K_0.5Co₃O₈, has been characterized by means of extended X-ray absorption fine structure spectroscopy. The crystal structure has been refined by rietveld analysis of X-ray powder diffraction data. The refined structure is similar to that of the tetragonal form of YBa₂Cu₃O_γ. The two independent cobalt ions have an octahedral and a five-co-ordinate environment of oxide ions, respectively. The potassium ions are located in the Ba²⁺ site.