Фазовая диаграмма системы Cd-Se

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Cd-Se (Cadmium-Selenium) R.C. Sharma and Y.A. Chang The Cd-Se system is characterized by a congruently melting intermediate phase, aCdSe, at 50 at.% Se. There is a liquid miscibility gap in the aCdSe-Se region of the phase diagram resulting in a monotectic reaction. Also, there are two eutectics close to pure Cd and pure Se, respectively. The assessed Cd-Se phase diagram is based on thermodynamic modeling and calculations, with review of the experimental data [62Rei, 67Sys]. There is good agreement between the calculated diagram and the available experimental data. The melting points of pure Cd and pure Se are 321.108 and 221 C, respectively. The mutual solid solubilities of Cd and Se have not been experimentally determined and are most likely to be negligible. The aCdSe phase is formed at 50 at.% Se and melts congruently. The deviation from stoichiometric composition in aCdSe is negligible [62Rei]. The aCdSe phase (wurtzite structure) transforms to bCdSe phase (NaCl structure) at high pressures at ~25 kbar at room temperature [63Jay]. [63Jay] also determined the melting equilibria of aCdSe and bCdSe phases as a function of pressure, and [69Ono] have determined the aCdSe to bCdSe transition pressure as a function of temperature, up to 700 C. [63Jay] gives the L-aCdSe-bCdSe triple point at ~13 kbar and ~1252 C. 62Rei: A. Reisman, M. Berkenblit, and M. Witzen, J. Phys. Chem., 66, 2210-2214 (1962). 63Jay: A. Jayaraman, W. Klement, and G.C. Kennedy, Phys. Rev., 130(6), 2277- 2283 (1963). 63Mar: A.N. Mariano and E.P. Warekois, Science, 142, 672-673 (1963). 63Roo: C.J.M. Rooymans, Phys. Lett., 4(3), 186-187 (1963). 67Sys: L.A. Sysoev, E.K. Raiskin, and V.R. Gur'ev, Izv. Akad. Nauk SSSR, Neorg. Mater., 3(2), 390-391 (1967) in Russian; TR: Inorg. Mater., 3(2), 341-342 ( 1967). 69Ono: A. Onodera, Rev. Phys. Chem. Jpn., 39(2), 65-77 (1969). 76Ree: R.R. Reeber, J. Mater. Sci., 11, 590-591 (1976). Submitted to the APD Program. Complete evaluation contains 4 figures, 7 tables, and 28 references. Special Points of the Cd-Se System