Phase equilibria in the Cu2Se–SnSe–Sb2Se3 quasi-ternary system has been studied by differential thermal analysis and powder X-ray diffraction. Some polythermal sections, isothermal sections at 300 K of the phase diagram and the projection of the liquidus surface are constructed. The regions of primary crystallization of phases, the nature and temperatures of non- and monovariant equilibria have been determined. The phase diagram of the SnSe–CuSbSe2 quasi-binary section has been refined. It was found that a quaternary compound CuSnSbSe3 is formed in the system by the peritectic reaction. This compound exists in a narrow range ~(650–723 K) temperatures. In addition, in the studied Cu2Se–SnSe–Sb2Se3 system, limited regions of solid solutions based on the SnSe, Sb2Se3, CuSbSe2 and SnSb2Se4 compounds have also been revealed
doi.org/10.32737/0005-2531-2022-1-73-82