The binary Laves phases ScCo 2 (MgCu 2 type) and TaCo 2 (MgNi 2 type) show solid solutions with indium; synthesis of Sc 1− x In x Co 2 samples in sealed tantalum tubes results in tantalum uptake from the container material. Ternary and quaternary samples of these Laves phases were synthesized by direct reactions of the elements followed by different annealing sequences in induction or muffle furnaces. The following structures were refined from single-crystal X-ray diffractometer data: Sc 0.08 In 0.19 Ta 0.73 Co 2 , Sc 0.26 In 0.5 Ta 0.24 Co 2 , Sc 0.25 In 0.34 Ta 0.41 Co 2 (all MgCu 4 Sn type, F 4‾$‾{4}$3 m ); Sc 0.53 Ta 0.47 Co 2 (MgCu 2 type, Fd 3‾$‾{3}$ m ); Sc 0.5 In 0.5 Co 2 , Sc 0.51 In 0.49 Co 2 , Sc 0.63 In 0.37 Co 2 and Sc 0.48 Ta 0.52 Co 2 (Sc 0.5 In 0.5 Co 2 type, P 6 3 mc ); Sc 0.63 In 0.15 Ta 0.22 Co 2 and Sc 0.49 In 0.28 Ta 0.23 Co 2 (new type, P 6 3 mc , non-centrosymmetric ordering variant of MgNi 0.9 Cu 1.1 ). The superstructure formation of the MgNi 0.9 Cu 1.1 variant is discussed on the basis of a group-subgroup scheme along with crystal chemical details on Laves phases.

中文翻译：

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Laves 相在系统 ScCo2-“InCo2”-TaCo2 中形成

二元Laves相ScCo 2 (MgCu 2 型)和TaCo 2 (MgNi 2 型)显示与铟的固溶体；在密封的钽管中合成 Sc 1− x In x Co 2 样品导致从容器材料中吸收钽。这些 Laves 相的三元和四元样品是通过元素的直接反应合成的，然后在感应炉或马弗炉中进行不同的退火序列。以下结构是从单晶 X 射线衍射仪数据中提炼出来的： Sc 0.08 In 0.19 Ta 0.73 Co 2 , Sc 0.26 In 0.5 Ta 0.24 Co 2 , Sc 0.25 In 0.34 Ta 0.41 Co 2 （全为 MgCu 4 Sn 型） ‾$‾{4}$3 百万); Sc 0.53 Ta 0.47 Co 2 (MgCu 2 型，Fd 3‾$‾{3}$ m )；Sc 0.5 In 0.5 Co 2 、Sc 0.51 In 0.49 Co 2 、Sc 0.63 In 0.37 Co 2 和Sc 0.48 Ta 0.52 Co 2 (Sc 0.5 In 0.5 Co 2 型，P 6 3 mc )；Sc 0.63 In 0.15 Ta 0.22 Co 2 和 Sc 0。49 In 0.28 Ta 0.23 Co 2 （新型，P 6 3 mc ，MgNi 0.9 Cu 1.1 的非中心对称有序变体）。MgNi 0.9 Cu 1.1 变体的超结构形成基于组-亚组方案以及Laves 相的晶体化学细节进行了讨论。