The solid solution structure of BiSrxCa1-xO2.50

The formation and solid-solution structure of BiSrxCa1-xO2.50 were studied by powder XRD analysis, and the crystallographic data of the phase are given. The crystal structure of BiSrxCa1-xO2.50 belongs to the monoclinic system with space group P1m1 or P12/m1, and the cell parameters for BiCaO2.50 (x = 0.00) are a = 1.8363 nm, b = 0.5366 nm, c = 1.4670 nm and beta = 100.26 degrees. BiSrxCa1-xO2.50 is a solid solution of Bi-Ca-O and Bi-Sr-O. When the strontium solid solubility Sr/Sr+Ca=0.50, the strontium dissolved in the phase reaches saturation, while the strontium solid solubility limit of the phase is between 0.67 and 0.75. Beyond this limit the crystal structure is greatly distorted. 9 refs.