Using differential thermal analysis and X-ray diffraction technique phase equilibria in the SnSb₂Te₄–SnBi₂Te₄ system were investigated and its T–x diagram was constructed. The system is non-quasibinary due to the incongruent melting of the starting ternary compounds, but it is stable below solidus. The system characterized by a continuous series of substitutional solid solutions with tetradimite-like hexagonal structure. The crystal lattice parameters are a linear function of the composition. Liquidus consists of one curve corresponding to the primary crystallization of solid solutions based on the SnTe compound (α-phase), which interacts with the liquid phase by peritectic reaction (L+ α↔γ) and forms solid solutions based on the SnSb₂Te₄ and SnBi₂Te₄ compounds.  According to the results of powder diffraction patterns, the lattice parameters are determined. It was established that the crystal lattice parameters of solid solutions vary linearly with composition

doi.org/10.32737/0005-2531-2019-4-6-10