Phases and their Relations in the YO_(1.5)-BaO(BaCO_3)-SrO-CuO System

摘要

Phases and their relations in the YO_(1.5)-BaO(BaCO_3)-SrO-CuO system at 900 deg C in air have been studied mainly by the powder X-ray diffraction method. It was found that two new phases with compositions of (Y, Ba, Sr)_2CuO_2(CO_3)_y, B_(s.s), and Y: Ba: Sr: Cu = 0.5: 0.7: 1.0: 1.0, N, formed in this system. The newly found phase B_(s.s) was isostructural with the oxycarbonate Sr_2CuO_2(CO_3). The phase N has an orthorombic sturucture with lattice parameters of a=3.855A, b=3.764A, and c=12.69A.