Reciprocal system 3Tl2S + Sb2Se3 ⇆ 3Tl2Se + Sb2S3

Phase equilibria in the reciprocal system 3Tl2S + Sb2Se3 ⇆ 3Tl2Se + Sb2S3 are investigated by DTA, X-ray powder diffraction, and emf measurements. Some polythermal sections, the isothermal section of the phase diagram at 400K, and the liquidus-surface projection for this system are constructed. The types and coordinates of invariant and univariant equilibria are determined. It is shown that the system is non-diagonal. Broad regions of solid solutions are found on the basis of the binary compounds Tl2S and Tl2Se and along the boundary system Sb2S3-Sb2Se3 and the sections Tl3SbS3-Tl3SbSe3, TlSbS2-TlSbSe2, and TlSb3S5-TlSb3Se5 of the phase diagram.