30 kbar Phase Equilibria of the La2O3–SrO–CuO System at 950°C
Abstract:Phase equilibria of the La2O3–SrO–CuO system have been determined at 950°C at 30 kbar (3 GPa). Stable phases at the apexes of the ternary phase diagram are CuO, La2O3, and SrO. Stable intermediate phases are La2, CuO4 and La2Cu2O5 in the LaO1.5–CuO binary and Sr2CuO3, SrCuO2, and Sr14Cu24O41 in the CuO–SrO binary. The La2–xSrx-CuO4– solid solution is stable for 0.00 is ≤x≤ 1.29, the La2–xSr1+xCu2O6+ solid solution is stable for 0.03 ≤x≤0.20, the La2–xSrxCu2O5– solid solution is stable for 0.00 ≤x≤1.08, and the LaxSr14–xCu24O41 solid solution is stable for 0.00 ≤x≤ 6.15. The 30 kbar phase diagram differs from the 1 atm (0.1 MPa) and 10 kbar (1 GPa) results principally in the absence of La1–xSr2+xCu2O5.5+ as a stable phase and the extended range of the La2–xSrxCu2O5– solid solution at 30 kbar.
Document Type: Research Article
Affiliations: Department of Chemistry and the Texas center for Superconductivity University of Houston, Houston, Texas 77204
Publication date: January 1, 1997