Phase diagram of the NdO_1.5-SrO-CuO system

Abstract

Subsolidus phase diagram of the NdO_1.5-SrO-CuO system was studied at 980°C and 1080°C in Air. One ternary compound Sr_1.08Nd_1.92Cu₂O_6-δ, and three solid solutions exist; Sr_14-xNd_xCu₂₄O_41+δ, (0 ?? x ?? 6.0 at 980°C), Sr_2-xNd_1+xCu₂O_5.5+δ(0.05 ?? x ?? 0.20 at 980°C; 0.05 ?? x ?? 0.35 at 1080°C), and Sr_2-xNd_xCuO_3+δ (x=2/3 at 980°C; 0.5 ?? x ?? 0.95 at 1080°C).Sr_2-xNd_xCuO_3+δ which crystallizes in the oxygen deficient K₂NiF₄ structure shows a unique modulated structure, The origin of the modulated structure is suggested to be a large lattice mismatch between the (Sr, Nd)₂O₂ and the CuO_1+δ layer.