Subsolidus phase relations of Bi2O3Nd2O3CuO

The subsolidus phase relations of the Bi2O3-Nd2O3-CuO ternary system and its binary systems along with crystallographic parameters of the compounds were investigated by X-ray powder diffraction and differential thermal analysis. The room temperature section of the phase diagram of the Bi2O3-Nd2O3-CuO system can be divided into two diphase regions and six triphase regions. No ternary compound was found. There exist two solid solutions (alpha, beta) and a compound Bi0.55Nd0.45O1.5 in the (Bi2O2)(1-x)(Nd2O3)(x) system. Both solid solution alpha (0.05 less than or equal to x less than or equal to 10.30) and beta (0.53 less than or equal to x less than or equal to 0.73) belong to the rhombohedral system (R (3) over bar m). The lattice parameters represented by a hexagonal cell are a = 3.9832(4), c = 27.536(5) Angstrom for Bi0.8Nd0.2O1.5 (alpha phase) and a = 3.8826(3), c = 9.727(1) Angstrom for Bi0.4Nd0.8O1.5 (beta phase). The Bi0.55Nd0.45O1.5 compound crystallizes in a face-centered cubic (f.c.c.) lattice with a = 5.5480(2) Angstrom.