Zhao Dan, Zhang Hao, Xie Zhi, Zhang Wei-Long, Yang Song-Ling, Cheng Wen-Dan
Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fujian 350002, China.
Dalton Trans. 2009 Jul 21(27):5310-8. doi: 10.1039/b822336j. Epub 2009 May 19.
Three ternary metal diorthophosphates (V), AM(PO(4))(2) (A = Sr, M = Ti, Sn; A = Ba, M = Sn), have been prepared by high-temperature solution growth (HTSG) method and structurally characterized by single-crystal X-ray diffraction analysis for the first time. The structure of BaSn(PO(4))(2) features the yavapaiite-type structure, with space group C2/m and a = 8.214(2), b = 5.2456(13), c = 7.8938(19) A, beta = 94.561(4) degrees , Z = 2, R(1) (all data) = 0.0253. Compounds SrM(PO(4))(2) (M = Ti, Sn) are isostructural and crystallize in a novel distorted yavapaiite structure, with space group C2/c and a = 16.4617(4), b = 5.1720(3), c = 8.1187(2) A, beta = 116.40(2) degrees , Z = 4, R(1) (all data) = 0.016 for SrTi(PO(4))(2); a = 16.674(14), b = 5.223(4), c = 8.099(6) A, beta = 115.821(11) degrees , Z = 4, R(1) (all data) = 0.025 for SrSn(PO(4))(2). Band structure calculations from the density functional theory (DFT) method indicate that all three compounds are approximately direct band-gap insulators.
通过高温溶液生长（HTSG）法制备了三种三元金属二正磷酸盐（V），即AM(PO₄)₂（A = Sr，M = Ti，Sn；A = Ba，M = Sn），并首次通过单晶X射线衍射分析对其进行了结构表征。BaSn(PO₄)₂的结构具有雅瓦派石型结构，空间群为C2/m，a = 8.214(2)，b = 5.2456(13)，c = 7.8938(19) Å，β = 94.561(4)°，Z = 2，R(1)（所有数据）= 0.0253。化合物SrM(PO₄)₂（M = Ti，Sn）是同构的，结晶为一种新型扭曲的雅瓦派石结构，空间群为C2/c，对于SrTi(PO₄)₂，a = 16.4617(4)，b = 5.1720(3)，c = 8.1187(2) Å，β = 116.40(2)°，Z = 4，R(1)（所有数据）= 0.016；对于SrSn(PO₄)₂，a = 16.674(14)，b = 5.223(4)，c = 8.099(6) Å，β = 115.821(11)°，Z = 4，R(1)（所有数据）= 0.025。基于密度泛函理论（DFT）方法的能带结构计算表明，这三种化合物均为近似直接带隙绝缘体。
