Investigation of the Pr2Se3-Cu2Se-PbSe and Pr2Se3-Ag2Se-PbSe systems

Phase diagram of the Cu2Se-PbSe system was constructed using differential-thermal analysis, X-ray diffraction and metallography. The eutectic reaction L double left right arrow beta-Cu2Se + PbSe takes place at 886 K and corresponds to 46 mol% PbSe. The peritectoid reaction beta-Cu2Se + PbSe double left right arrow alpha-Cu2Se takes place at 420 K. The formation of the PrCuSe2 compound (LaCuS2 structure type, space group P2(1)/c) and the solid solution range Pr2Se3-Pr2PbSe4 (Th3P4 structure type, space group I (4) over bar 3d, a = 0.89916(2) nm, R-I = 0.0682 for Pr2PbSe4) was confirmed using X-ray powder diffraction. The interactions between the components in the Pr2Se3-Cu2Se-PbSe and Pr2Se3-Ag2Se-PbSe systems at 870 K were determined using X-ray powder diffraction. No quaternary compounds exist in these systems. (c) 2005 Elsevier B.V. All rights reserved.