Stetskiv Andrij, Tarasiuk Ivan, Rozdzynska-Kielbik Beata, Oshchapovsky Igor, Pavlyuk Volodymyr
Acta Crystallogr Sect E Struct Rep Online. 2012 Feb 1;68(Pt 2):i16. doi: 10.1107/S1600536812002103. Epub 2012 Jan 21.
The new terbium (lithium zinc) distannide, TbLi(1-x)Zn(x)Sn(2) (x = 0.2) crystallizes in the ortho-rhom-bic CeNiSi(2) structure type with space group Cmcm and Pearson symbol oS16. Of the four independent 4c atom positions (m2m site symmetry), three are fully occupied by individual atoms (two by Sn and one by Tb atoms) and the fourth is occupied by Li and Zn atoms with a statistical distribution. The Tb coordination polyhedron is a 21-vertex pseudo-Frank-Kasper polyhedron. One Sn atom is enclosed in a tricapped trigonal prism, the second Sn atom is in a cubocta-hedron and the statistically distributed (Li,Zn) site is in a tetra-gonal anti-prism with one added atom. Electronic structure calculations were used for the elucidation of reasons for and the ability of mutual substitution of lithium and transition metals. Positive charge density was observed around the rare earth atom and the Li and Zn atoms, the negative charge density in the proximity of the Sn atoms.
新型铽（锂锌）二锡化物TbLi(1-x)Zn(x)Sn₂（x = 0.2）以正交晶系的CeNiSi₂结构类型结晶，空间群为Cmcm，皮尔逊符号为oS16。在四个独立的4c原子位置（m2m点群对称性）中，三个被单个原子完全占据（两个被Sn原子占据，一个被Tb原子占据），第四个位置被Li和Zn原子统计分布占据。Tb的配位多面体是一个21顶点的伪弗兰克-卡斯珀多面体。一个Sn原子被包含在一个三帽三角棱柱中，第二个Sn原子在一个立方八面体中，统计分布的（Li,Zn）位置在一个添加了一个原子的四方反棱柱中。电子结构计算用于阐明锂和过渡金属相互替代的原因及能力。在稀土原子以及Li和Zn原子周围观察到正电荷密度，在Sn原子附近观察到负电荷密度。
