Synthesis and Structural Characterization of Ba7Li11Bi10 and AE4(Li,Tr)7Pn6 (AE = Sr, Ba, Eu; Tr = Ga, In; Pn = Sb, Bi)
Synthesis and Structural Characterization of Ba7Li11Bi10 and AE4(Li,Tr)7Pn6 (AE = Sr, Ba, Eu; Tr = Ga, In; Pn = Sb, Bi)
复制标题
Ba7Li11Bi10 和 AE4(Li,Tr)7Pn6 (AE = Sr, Ba, Eu;Tr = Ga, In;Pn = Sb, Bi) 的合成和结构表征
作者：
D. Ojwang;S. Bobev
报道了具有单斜空间群C2/m (a = 18.407(3) Å， b = 5.0258(9) Å， c = 18.353(3) Å的单晶型新型三元化合物Ba7Li11Bi10的合成和晶体结构；β = 104.43(1)°；Pearson符号mS56)，以及结构相关的四相Ba4(Li1−xGax)7Sb6, Ba4(Li1−xInx)7Sb6, Ba4(Li1−xInx)7Bi6和Eu4(Li1−xInx)7Bi6(结晶为Eu4Li7Bi6结构类型，具有相同的单斜空间群C2/m (a = 18.4045(13) -17.642 (4) Å， b = 5.012(4) -4.8297 （10） Å， c = 13.2792(10) -12.850 (3) Å， β = 126.80（1) -125.85(1)°）；皮尔逊符号mS34)。所有研究的化合物都是在相应元素的高温反应产物中鉴定出来的。这两种晶体结构都是基于角和边连接的锂中心Sb4（或Bi4）四面体，Sb6（或Bi6）八面体和Sb2或Bi2哑铃。考虑到这两种结构之间的相似性，可以认为它们是用通式（BaLi3Sb2）n(Ba3Li4Sb4)m或（BaLi3Bi2）n(Ba3Li4Bi4)m描述的潜在大的同源序列中最简单的成员，其中更复杂的“7-11-10”相是n = 2和m = 1的成员，而“4-7-6”相是两个组分以等比例共生。讨论了计算得到的Ba7Li11Bi10和理想的Ba4Li7Bi6 （Ba4(Li1−xInx)7Bi6的模型）的能带结构。
Reported are the synthesis and crystal structure of Ba7Li11Bi10, a new ternary compound crystallizing in its own type with the monoclinic space group C2/m (a = 18.407(3) Å, b = 5.0258(9) Å, and c = 18.353(3) Å; β = 104.43(1)°; Pearson symbol mS56), and those of the structurally related quaternary phases Ba4(Li1−xGax)7Sb6, Ba4(Li1−xInx)7Sb6, Ba4(Li1−xInx)7Bi6, and Eu4(Li1−xInx)7Bi6 (crystallizing in the Eu4Li7Bi6 structure type with the same monoclinic space group C2/m (a = 18.4045(13)–17.642(4) Å, b = 5.012(4)–4.8297(10) Å, and c = 13.2792(10)–12.850(3) Å, β = 126.80(1)–125.85(1)°; Pearson symbol mS34). All studied compounds are identified among the products of the high-temperature reactions of the corresponding elements. Both types of crystal structures are based on corner- and edge-linked Li-centered Sb4 (or Bi4) tetrahedra, Sb6 (or Bi6) octahedra, and Sb2 or Bi2 dumbbells. Given the similarities between the two structures, it might be proposed that they represent the simplest members of a potentially large homologous series described with the general formulae (BaLi3Sb2)n(Ba3Li4Sb4)m or (BaLi3Bi2)n(Ba3Li4Bi4)m, where the more complicated “7-11-10” phase is the member with n = 2 and m = 1, while the “4-7-6” one is the intergrowth of the two components in an equal ratio. The computed electronic band structures of Ba7Li11Bi10 and idealized Ba4Li7Bi6 (a model for Ba4(Li1−xInx)7Bi6) are also discussed.