Mills Allison M, Ruck Michael
Institut für Anorganische Chemie, Technische Universität Dresden, D-01062 Dresden, Germany.
Inorg Chem. 2006 Jun 26;45(13):5172-8. doi: 10.1021/ic0521372.
The compounds Ce53Fe12S90X3 (X = Cl, Br, I), which represent the first examples of rare-earth transition-metal sulfide halides, were prepared using the reactive-flux method, through reaction of Ce2S3, FeS, or Fe and S in a CeX3 flux at 1320 K. Their structures were determined by single-crystal X-ray diffraction. The compounds are isostructural, crystallizing in the trigonal space group Rm with Z = 1 [Ce53Fe12S90Cl3, a = 13.9094(9) A, c = 21.604(2) A, V = 3619.7(4) A3; Ce(53)Fe(12)S(90)Br(3), a = 13.916(1) A, c = 21.824(2) A, V = 3660.0(5) A3; Ce53Fe12S90I3, a = 13.863(3) A, c = 21.944(6) A, V = 3652(2) A3]. The structure adopted is a stuffed variant of the La52Fe12S90 structure type. Fe2S9 dimers of face-sharing octahedra are linked by face- and vertex-sharing capped CeS6 trigonal prisms, forming a three-dimensional framework containing cuboctahedral cavities of two sizes. The smaller cavities accommodate alternative sites for disordered cerium atoms. The larger cavities, which remain empty in the parent structure, are filled by halogen atoms in Ce53Fe12S90X3. Alternatively, the structure can be described as a 9-fold superstructure of the Mn5Si3 structure type (P6(3)/mcm), with a = a' and c = 3c'. Temperature-dependent magnetic susceptibility measurements suggest that Ce53Fe12S90I3 may order antiferromagnetically at low temperatures.
化合物Ce53Fe12S90X3（X = Cl、Br、I）是稀土过渡金属硫卤化物的首个实例，采用反应助熔剂法，通过在1320 K的CeX3助熔剂中使Ce2S3、FeS或Fe与S反应制备而成。其结构通过单晶X射线衍射确定。这些化合物同构，结晶于三方空间群Rm，Z = 1 [Ce53Fe12S90Cl3，a = 13.9094(9) Å，c = 21.604(2) Å，V = 3619.7(4) Å3；Ce(53)Fe(12)S(90)Br(3)，a = 13.916(1) Å，c = 21.824(2) Å，V = 3660.0(5) Å3；Ce53Fe12S90I3，a = 13.863(3) Å，c = 21.944(6) Å，V = 3652(2) Å3]。所采用的结构是La52Fe12S90结构类型的一种填充变体。共面八面体的Fe2S9二聚体通过共面和共顶点的盖帽CeS6三角棱柱相连，形成一个包含两种尺寸立方八面体空穴的三维框架。较小的空穴容纳无序铈原子的替代位置。在母体结构中保持为空的较大空穴在Ce53Fe12S90X3中被卤素原子填充。或者，该结构可描述为Mn5Si3结构类型（P6(3)/mcm）的9倍超结构，a = a'且c = 3c'。与温度相关的磁化率测量表明，Ce53Fe12S90I3在低温下可能发生反铁磁有序。
