Фазовая диаграмма системы Ce-Ge

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Ce-Ge (Cerium-Germanium) A.B. Gokhale and G.J. Abbaschian The assessed Ce-Ge phase diagram is based mainly on the work of [71Ere] and [ 72Ere]. The Ce-Ge system is characterized by: (1) the intermediate phases Ce3Ge, Ce5Ge3, Ce4Ge3, Ce5Ge4, CeGe, and CeGe2-x. Ce3Ge forms peritectically at 790 C; Ce5Ge3 melts congruently at 1500 C; Ce4Ge3 and Ce5Ge4 form through peritectoid reactions at 1293 and 1345 C, respectively; CeGe forms peritectically at 1433 C; and CeGe2-x melts congruently at 1513 C; (2) three eutectic reactions occur between (Ce) and Ce3Ge at 670 C and 11 at.% Ge, between CeGe and CeGe2-x at 1340 C and 51 at.% Ge, and between CeGe2-x and ( Ge) at 810 C and 84 at.% Ge; and (3) CeGe2-x undergoes a polymorphic transformation at 560 C on the Ge-deficient side and at 490 C at the Ge-rich side. The solid solubility of Ge in (Ce) appears to be negligible [71Ere, 72Ere]. The (Ge) solid solution dissolves a maximum of ~0.5 at.% Ce at the eutectic temperature of 810 C [71Ere]. According to [64Rug], Ce3Ge, Ce5Ge3, CeGe, and CeGe2-x obey the Curie-Weiss law at temperatures >80 K. In addition, [67Bus] and [82Kre] observed a remnant magnetic moment for Ce5Ge3 at 4.2 K. 64Gla: E.I. Gladyshevskii, Izv. Nauka, 141-143 (1964) in Russian; TR: U.S. Dept. Commerce JPRS-28849, 184-187 (1964). 64Rug: A.F. Ruggiero and G.L. Olcese, Atti. Accad. Naz. Lincei, Rend., 37, 169- 174 (1964) in Italian. 65Par: E. Parthe, D. Hohnke, W. Jeitschko, and O. Schob, Naturwissenshaften, 52(7), 155 (1965). 66Has: H. Haschke, H. Nowotny, and F. Benesovsky, Monatsh. Chem., 97, 1452- 1458 (1966). 67Bus: K.H.J. Buschow and J.F. Fast, Phys. Status Solidi, 21, 593-600 (1967). 71Ere: V.N. Eremenko, K.S. Zyong, Yu.I. Buyanov, and A.M. Khar'kova, Poroshk. Metall., 9, 46-49 (1971) in Russian; TR: Sov. Powder Metall. Met. Ceram., 10, 717-719 (1971). 72Ere: V.N. Eremenko, Z.K. Shi, Yu.I. Buyanov, and A.M. Khar'kova, Dop. Akad. Nauk Ukr. RSR B, 34, 1080-1084 (1972) in Russian. 82Kre: R.P. Krentsis, S.M. Barmin, A.A. Sevast'yanov, and P.V. Gel'd, Fiz. Tverd. Tela, 24, 2856-2859 (1982) in Russian; TR: Sov. Phys. Solid State, 24, 1620-1621 (1982). Published in Bull. Alloy Phase Diagrams, 10(2), Apr 1989. Complete evaluation contains 1 figure, 3 tables, and 28 references. Special Points of the Ce-Ge System