Abstract The copper-rich intermetallic compounds CaCu9Mg2 and SrCu9Mg2 were synthesized by induction melting of the elements and subsequent annealing in a muffle furnace. CaCu9Mg2 and SrCu9Mg2 crystallize with the TbCu9Mg2 type structure, space group P 63/mmc, which is a ternary ordered variant of CeNi3. The polycrystalline samples were characterized through their X-ray powder patterns. The CaCu9Mg2 structure was refined from single-crystal X-ray diffraction data. a = 504.13(9), c = 1622.5(3) pm, wR2 = 0.0635, 302 F2 values and 19 variables. The two striking coordination polyhedra in the CaCu9Mg2 structure are Ca@Cu18Mg2 and Mg@Cu12Mg3Ca. These polyhedra condense to layers which are stacked in ABA′B′ sequence. The X-ray data give no hint for Ca/Mg mixing.

中文翻译：

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CaCu9Mg2 和 SrCu9Mg2 中碱土金属的排序

摘要 通过对元素进行感应熔化，然后在马弗炉中退火，合成了富铜金属间化合物 CaCu9Mg2 和 SrCu9Mg2。CaCu9Mg2 和 SrCu9Mg2 结晶为 TbCu9Mg2 型结构，空间群 P 63/mmc，是 CeNi3 的三元有序变体。多晶样品通过它们的 X 射线粉末图案进行表征。CaCu9Mg2 结构是从单晶 X 射线衍射数据中提炼出来的。a = 504.13(9), c = 1622.5(3) pm, wR2 = 0.0635, 302 F2 值和 19 个变量。CaCu9Mg2 结构中两个引人注目的配位多面体是 Ca@Cu18Mg2 和 Mg@Cu12Mg3Ca。这些多面体凝聚成以 ABA'B' 序列堆叠的层。X 射线数据没有提示 Ca/Mg 混合。