Yokota Kaori, Watanuki Ryuta, Nakashima Miki, Uehara Masatomo, Gouchi Jun, Uwatoko Yoshiya, Umehara Izuru
Department of Physics, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan.
Department of Chemistry, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan.
Acta Crystallogr E Crystallogr Commun. 2020 Mar 10;76(Pt 4):510-513. doi: 10.1107/S2056989020002789. eCollection 2020 Apr 1.
The crystal structures of praseodymium silicide (5/4), PrSi, and neodymium silicide (5/4), NdSi, were redetermined using high-quality single-crystal X-ray diffraction data. The previous structure reports of PrSi were only based on powder X-ray diffraction data [Smith (1967 ▸). 940-943; Yang (2002 ▸). , 189-194; Yang , (2003 ▸). , 146-153]. On the other hand, the structure of NdSi has been determined from powder data [neutron; Cadogan , (2002 ▸). , , 7191-7200] and X-ray [Smith (1967 ▸). 940-943; Yang (2002 ▸). , 189-194; Yang , (2003 ▸). , 146-153] and single-crystal data with isotropic atomic displacement parameters [Roger , (2006 ▸). , 73-84]. In addition, the anisotropic atomic displacement parameters for all atomic sites have been determined for the first time. These compounds are confirmed to have the tetra-gonal ZrSi-type structure (space group: 422), as reported previously (Smith , 1967 ▸). The structure is built up by distorted body-centered cubes consisting of Pr(Nd) atoms, which are linked to each other by edge-sharing to form a three-dimensional framework. This framework delimits zigzag channels in which the silicon dimers are situated.
使用高质量的单晶X射线衍射数据重新测定了硅化镨（5/4）PrSi和硅化钕（5/4）NdSi的晶体结构。先前关于PrSi的结构报道仅基于粉末X射线衍射数据[史密斯（1967▸），940 - 943；杨（2002▸），189 - 194；杨（2003▸），146 - 153]。另一方面，NdSi的结构已由粉末数据[中子；卡多根（2002▸），，7191 - 7200]以及X射线[史密斯（1967▸），940 - 943；杨（2002▸），189 - 194；杨（2003▸），146 - 153]和具有各向同性原子位移参数的单晶数据[罗杰（2006▸），73 - 84]确定。此外，首次确定了所有原子位置的各向异性原子位移参数。如先前报道（史密斯，1967▸），这些化合物被证实具有四方ZrSi型结构（空间群：422）。该结构由由Pr（Nd）原子组成的扭曲体心立方体构成，这些立方体通过边共享相互连接形成三维框架。这个框架界定了之字形通道，硅二聚体位于其中。
