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PbTe–Bi2Te3–Sb2Te3 system has been studied by DTA and X-ray diffraction methods along the PbBi2Te4 – "PbSb2Te4" section. It was found that the compound of the composition PbSb2Te4, specified in the literature does not exist. On the basis of the latter a wide (more than 50 mol%) area of solid solution (γ) was detected. By using obtained experimental results, a fragment of the solid-phase equilibrium diagram of the PbTe–Bi2Te3–Sb2Te3 system was constructed and boundaries of the heterogeneous areas α+γ, α+β, α+β+γ (α- and β- are solid solutions based on PbTe and Sb2Te3, respectively) have been determined

A newly refined version of the phase diagram of the PbTe–Bi2Te3 pseudo-binary system was construc-ted using differential thermal analysis (DTA) and X-ray diffraction (XRD) techniques. It was established that the system forms three tetradymite-type layered ternary compounds, namely PbBi2Te4, PbBi4Te7, and PbBi6Te10, and all these phases melt with peritectic decomposition. However, earlier reported Pb3Bi4Te9, Pb2Bi6Te11, and PbBi8Te13 compounds were not confirmed in our XRD studies. The existence of homogeneity areas based on all ternary compounds and the starting phases PbTe and Bi2Te3 was detected. The crystal structure of the ternary compounds was solved by Rietveld refinement. The newly constructed phase diagram provides very valuable information for choosing appropriate conditions for the synthesis of bulk samples or single crystals growth

Two-phase alloys Bi8Te9+Bi4Te5 and BiTe+Bi8Te9 were studied by the electromotive forces method (EMF) in the temperature range 300-450 K. From the EMF data, the relative partial molar functions of bismuth in the alloys were calculated. The potential-forming reactions responsible for these partial functions were compiled, the values of the standard thermodynamic functions of formation, and the standard entropies of Bi8Te9 and BiTe compounds were calculated. A comparative analysis of the data for BiTe with the literature data was carried out; for Bi8Te9, the thermodynamic functions were obtained for the first time.