Фазовая диаграмма системы Sn-Te

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Sn-Te (Tin-Tellurium) R.C. Sharma and Y.A. Chang The assessed Sn-Te phase diagram is based on the work of [83Hsi]. SnTe, an intermediate phase with a narrow range of homogeneity, is formed around 50 at.% Te. A second-order phase transition occurs in SnTe at low temperatures. The critical temperature for this transformation is strongly dependent on the composition of the phase. It has been suggested by many investigators that this transformation is from the cubic NaCl-type structure to a rhombohedral structure. However, [75Val] has suggested that the transformation is from the cubic NaCl-type structure to an orthorhombic structure. [64Kaf] reported a first-order transformation of SnTe from a cubic (NaCl-type) to an orthorhombic structure (GeS-type) at 18 kbar pressure at room temperature. The transformation was accompanied by a 7% increase in density. [68Kab] reported a two-phase region (cubic plus orthorhombic) in the pressure range of 10 to 28 kbar, above which only the orthorhombic phase existed. The volume change for the cubic to orthorhombic transformation was reported to be ~2.5%. The liquidus in the Sn-SnTe region of the assessed diagram has an inflection point, which is indicative of a metastable liquidus miscibility gap at lower temperatures. This metastable liquid miscibility gap has been calculated by [ 83Hsi], but has not been verified experimentally. 64Kaf: J.A. Kafalas and A.N. Mariano, Science, 143, 952 (1964). 68Kab: S.S. Kabalkina, N.R. Serebryanaya, and L.F. Vereschchagin, Sov. Phys.- Solid State, 10, 574-579 (1968). 75Val: O. Valassiades and N.A. Economou, Phys. Status Solidi, 30, 187-195 ( 1975). 83Hsi: K. Hsieh, M.S. Wei, and Y.A. Chang, Z. Metallkd., 74, 330-337 (1983). Published in Bull. Alloy Phase Diagrams, 7(1), Feb 1986. Complete evaluation contains 10 figures, 10 tables, and 54 references. Special Points of the Sn-Te System