Thorium-tin compounds

It will be seen that the enthalpy of formation of ThGe2(cr) around 1400 K, - 120.6 kJ-mor, derived from these measurements is very much less negative than the directly determined value noted above. It is difficult to explain this large discrepancy, especially as the data for ThSi2(cr) from the two same studies agree rather well, as noted in Section XI.2.1. No values have been selected by the review for the thorium germanide phases. 

Cirafici et al. [1983CIR/PAL] have studied the Th-Sn system, and no new phases have been reported since then. 

There are four phases in the system, with structures given in Table XI-11 [1983CIR/PAL]. 

Phase Symmetry, Space Group Structural type Lattice parameters (A) 

For ThSu3(cr), the results of [1983CIR/PAL] confirmed the structural data obtained earlier by [1958FER] who had reported a = 4.718 A, while [1970HAV/DAM] gave a = 4.714 A. This compound is isomorphous with USus, ThPbs, ThTh, and Thins. The most stable phase is ThsSus, which melts congruently at ca. 2073 K. 

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