Germanium, ternary systems

The phase relations in the Pr-Si-Ge ternary system at 873 K were investigated by Muratova and Bodak (1974) using X-ray powder analysis (fig. 22). Samples were obtained by arc melting, and homogenized at 873 K for 500 h. No ternary compounds were found, but a continuous solid solution Pr(Si,Ge)2- was observed. The solubilities of germanium... 

From 16 rare-earth ternary systems with lithium and germanium the isothermal sections for 10 systems have been established over the whole concentration region. 

Gryniv, I.O., A.S.Nogaand Yu.N. Grin , 1989, Ternary systems of gallium and germanium with rare earth (Ce) and transition (Mn) metals, in V Vsesoyuzn. Soveshch. Diagr. Sost. metal, system., Tezisy Dokl., Zvenigorod, 1989, p. 154. 

Muratova, L.A., 1976, Ternary systems (yttrium, lanthanum, cerium, praseodymium, gadolinium)-germanium-silicon, Ph.D. Chemistry Thesis (Lv iv University, Lv iv) pp. 1-17. 

The ternary systems of rare-earth metals with metallic and semimetallic components have been studied intensively during the last 20 years. Among them, the systems containing germanium are most completely investigated. 

The ternary systems with two rare-earth metals and germanium are characterized by the formation of compounds with compositions (R,R )5Ge4, (R,R )iiGeio, (R,R )Ge and (R,R )2Ge which crystallize with the structure types of binary compounds and their superstructures. This is caused by the similarities in the electronic structure of R elements. 

Another interesting observation is that the ternary alloy systems of the rare earths and germanium with the s and p elements have hardly been investigated. And of those that have been studied, only a few intermediate phases have been observed in the ternary systems. The chapter ends with a discussion of the general trends and unusual features observed in the various sets of ternary phase diagrams. 

Germanium appears to form no carbide, but it alloys with many metals and metalloids. A complete tabulation of intermetallic compounds (as of 1968)1 fists 152 compositions, from which the representative metal germanides of Table 5 have been abstracted. The relation of Ge with Si is unique a continuous series of solid solutions is formed, and the two liquids also form ideal mixtures. About eighty ternary intermetallic compounds are known, and phase diagrams for many of the binary and ternary systems have been reportedly. 

A total of 117 ternary compounds were found in the 17 R-M-Ge ternary systems while deriving the phase diagrams. They are described below. Another 146 ternary systems of the rare earths, germanium and a metallic element have only been partially investigated. The existence of an additional 393 ternary compounds was reported in the literature. Crystallographic data for these are given in table 4. The crystal structure was solved for 83 of the first 117 ternary compounds. 

Ternary systems with germanium more or less were studied with M = Li, Mn, Fe, Co, Ni, Cu, Ru, Rh, Pd, Os, Ir, Pt (see tables 9 and 4). A maximum number of ternary compounds are observed for cobalt and nickel. 

Salamakha, P.S., Sologub, O.L., Bodak, O.I. Ternary rare-earth-germanium systems, in Gschneid-ner Jr., K.A., Eyring, L., editors. Handbook on the Physics and Chemistry of Rare Earths, vol. 27. Amsterdam North-Holland 1999c, chap. 173. 

P.S. Salamakha, O.L. Sologub and O.I. Bodak, Ternary rare-earth-germanium systems 1... 

This section describes ternary chalcogenides of silicon, germanium, tin, lead, and indium systems. All of these elements, except indium, belong to Group 14 in the periodic table of elements and therefore, theoretically, all of them have stable +4 oxidation states. Thus, a substitution one element of Group 14 by another could result in a similar structure. However, structural relationships among the ternary compounds seem to not be as straightforward as this may appear. 

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