Phase diagram of the Bi–Sr–Cu–O system

The phases present in the Bi-Sr-Cu-O system in air, at 865 C, were investigated using X-ray diffraction techniques, with particular emphasis on the homogeneity ranges of the ternary oxide phases. Only three such phases were found; a tetragonal form and an orthorhombic form of Bi2Sr2CuO6 (both exhibiting homogeneity ranges), and Bi4Sr8Cu5Oz. Eight binary oxides were also found. No evidence was found at this temperature for the previously reported phases, Bi2Sr3Cu2Oz and Bi17Sr16Cu7Oy. 27 refs.