Fe_2BP_3O_(12)的合成及晶体结构

Synthesis and Crystal Structure of Fe_2BP_3O_12

采用固态反应方法合成了有序的铁基硼磷酸盐Fe2BP3O12,用X射线粉末衍射方法精修了其晶体结构,属三方晶系,空间群为P3,α=8.02703(6)°A,c=7.40168(9)°A,V=413.02(1)°A3,Dx=3.2758(1)(g/Cm3),Z=2,对于55个参数,用188条衍射线及18001个衍射强度全谱数据点精修到R(Ⅰ)=6.35％,R(p)=15.36％,所对应的R(dbw)=10.12％.B原子具有三角形氧配位,P和Fe的氧配位分别是四面体和八面体.Fe的两配位八面体共面形成新结构单元,BO3三角形联接磷氧和铁氧多面体形成三维结构.对比同构的铬硼磷酸盐,此化合物期望具有类似的非线性光学及其它非线性物理性质.

Fe2BP3O12 was synthesized by high temperature solid state reactions. Its crystal structure was refined by powder X-ray diffraction methods, belonging to trigonal system with space group P3, a=8.02703(6)Angstrom, c=7.40168(9)Angstrom(3), V=413-02(1)Angstrom(3), D-x=3.2758(1)(g/cm(3)), Z=2. The full profile refinement resulted to R(I)=6.35%, R(p)=15.36% and R(dbw)=10.12% for 55 parameters using 188 reflections and 18001 profile data points. The structure contains [BP3O12](4-). poly-anion, built by trigonal planar BO3 sharing the three corner oxygen atom with three PO4 tetrahedra. And Fe2O9 bi-octahedra fused by two face-sharing FeO6 connect with the poly-anions forming three dimensional ordered structure. Compared with its chromium isotypic compound, Cr2BP3O12, which shows NLO property, the title compound may be a potential NLO material.