Isaeva Anna, Ruck Michael, Schäfer Konrad, Rodewald Ute Ch, Pöttgen Rainer
Department of Chemistry and Food Chemistry, Technische Universität Dresden , 01062 Dresden, Germany.
Inorg Chem. 2015 Feb 2;54(3):885-9. doi: 10.1021/ic502205k. Epub 2014 Oct 22.
Crystals of Bi(4)Ir, a new intermetallic compound, were obtained by the reaction of an iridium-containing intermetallic precursor with liquid bismuth. X-ray diffraction on a single crystal revealed a rhombohedral structure [R3̅m, a = 2656.7(2) pm, and c = 701.6(4) pm]. Bi(4)Ir is not isostructural to Bi(4)Rh but combines motifs of the metastable superconductor Bi1(4)Rh(3) with those found in the weak topological insulator Bi1(4)Rh(3)I(9). The two crystallographically independent iridium sites in Bi(4)Ir have square-prismatic and skewed-square-antiprismatic bismuth coordination with Bi-Ir distances of 283-287 pm. By sharing common edges, the two types of [IrBi(8)] units constitute a complex three-dimensional network of rings and helices. The bonding in the heterometallic framework is dominated by pairwise Bi-Ir interactions. In addition, three-center bonds are found in the bismuth triangles formed by adjacent [IrBi(8)] polyhedra. Density functional theory based band-structure calculations suggest metallic properties.
通过含铱金属间前驱体与液态铋反应，获得了一种新型金属间化合物Bi(4)Ir的晶体。对单晶进行的X射线衍射显示其为菱面体结构[R3̅m，a = 2656.7(2)皮米，c = 701.6(4)皮米]。Bi(4)Ir与Bi(4)Rh不是同构的，而是将亚稳超导体Bi1(4)Rh(3)的结构基序与弱拓扑绝缘体Bi1(4)Rh(3)I(9)中的结构基序结合在一起。Bi(4)Ir中两个晶体学独立的铱位点具有方形棱柱和扭曲方形反棱柱的铋配位，Bi-Ir距离为283 - 287皮米。通过共享公共边，两种类型的[IrBi(8)]单元构成了一个由环和螺旋组成的复杂三维网络。异金属框架中的键合主要由成对的Bi-Ir相互作用主导。此外，在相邻[IrBi(8)]多面体形成的铋三角形中发现了三中心键。基于密度泛函理论的能带结构计算表明其具有金属性质。
