The intermetallic compound LaNi 11.8–11.4 Si 1.2–1.6 was synthesized by arc-melting and its crystal structure was determined using powder and single-crystal X-ray diffraction data. The compound adopts the cubic CaCu 6.5 Al 6.5 -type structure (space group Fm 3‾$\bar{3}$ c , Pearson code cF 112, Z = 8), which is a partially ordered ternary derivative of the NaZn 13 type: a = 11.256(4) Å, V = 1426.1(15) Å 3 , R = 0.0133, wR = 0.0285 for 93 reflections with I > 2 σ ( I ) for LaNi 11.4 Si 1.6 ; a = 11.25486(8) Å, V = 1425.68(2) Å 3 , R p = 4.17%, R wp = 5.85%, R B = 3.44% for LaNi 11.8 Si 1.2 . One of its crystallographic positions (96 i ) is occupied by a mixture of Ni and Si atoms. The structure of this new silicide can be represented as a packing of Ni-centered icosahedra and La-centered snub cubes, which are packed in a CsCl-related manner.

中文翻译：

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新型硅化物LaNi11.8–11.4Si1.2–1.6的晶体结构

通过电弧熔化合成了金属间化合物LaNi 11.8-11.4 Si 1.2-1.6，并使用粉末和单晶X射线衍射数据确定了其晶体结构。该化合物采用立方CaCu 6.5 Al 6.5型结构（空间群Fm 3‾ $ \ bar {3} $ c，Pearson码cF 112，Z = 8），是NaZn 13型的部分有序三元衍生物：对于LaNi 11.4 Si 1.6的I> 2σ（I）的93次反射，a = 11.256（4）Å，V = 1426.1（15）Å3，R = 0.0133，wR = 0.0285; 对于LaNi 11.8 Si 1.2，a = 11.25486（8）Å，V = 1425.68（2）Å3，R p = 4.17％，R wp = 5.85％，RB = 3.44％。Ni和Si原子的混合物占据其结晶位置之一（96 i）。这种新型硅化物的结构可以表示为以CsCl相关的方式包装的以Ni为中心的二十面体和以La为中心的缓冲立方体的堆积。