Suen Nian-Tzu, You Tae-Soo, Bobev Svilen
Department of Chemistry and Biochemistry, 304A Drake Hall, University of Delaware, Newark, DE 19716, USA.
Acta Crystallogr C. 2013 Jan;69(Pt 1):1-4. doi: 10.1107/S0108270112050032. Epub 2012 Dec 13.
The syntheses and single-crystal and electronic structures of three new ternary lithium rare earth germanides, RE(5-x)Li(x)Ge(4) (RE = Nd, Sm and Gd; x ≃ 1), namely tetrasamarium lithium tetragermanide (Sm(3.97)Li(1.03)Ge(4)), tetraneodymium lithium tetragermanide (Nd(3.97)Li(1.03)Ge(4)) and tetragadolinium lithium tetragermanide (Gd(3.96)Li(1.03)Ge(4)), are reported. All three compounds crystallize in the orthorhombic space group Pnma and adopt the Gd(5)Si(4) structure type (Pearson code oP36). There are six atoms in the asymmetric unit: Li1 in Wyckoff site 4c, RE1 in 8d, RE2 in 8d, Ge1 in 8d, Ge2 in 4c and Ge3 in 4c. One of the RE sites, i.e. RE2, is statistically occupied by RE and Li atoms, accounting for the small deviation from ideal RE(4)LiGe(4) stoichiometry.
报道了三种新型三元锂稀土锗化物RE(5-x)Li(x)Ge(4)（RE = Nd、Sm和Gd；x ≃ 1），即四钐锂四锗化物（Sm(3.97)Li(1.03)Ge(4)）、四钕锂四锗化物（Nd(3.97)Li(1.03)Ge(4)）和四钆锂四锗化物（Gd(3.96)Li(1.03)Ge(4)）的合成、单晶结构和电子结构。这三种化合物均结晶于正交空间群Pnma，采用Gd(5)Si(4)结构类型（皮尔逊编码oP36）。不对称单元中有六个原子：位于Wyckoff位置4c的Li1、位于8d的RE1、位于8d的RE2、位于8d的Ge1、位于4c的Ge2和位于4c的Ge3。其中一个RE位置，即RE2，由RE和Li原子统计占据，这解释了与理想的RE(4)LiGe(4)化学计量比的微小偏差。
