新金属间化合物Bi5MnPr3的晶体结构

摘要

The crystal structure of a new ternary compound Bi5 MnPr3 was determined by X-ray powder diffraction using the Rietveld method. The R-factors of Rietveld refinement were Rp = 10.79％ ,Rwp = 13.70％, RF = 5.99％ , RB = 8.36％ , respectively. The result showed that the ternary compound Bi5MnPr3 crystallizes in the hexagonal, space group P63/mcm( No. 193) with the Ce3MnBi5type structure and lattice parameters a =0.964 60( 1 )nm,c =0.646 501 (7)nm,formula units per unit cell Z =2,calculated density Dx =9.62 g/cm3. In the unit cell, Mn atoms occupy the 2b sites,some Bi atoms occupy the 4d sites,while other Bi atoms and Pr atoms are in the 6g sites respectively.%用X射线粉末衍射技术和Rietveld全谱图拟合法研究了新金属间化合物Bi5MnPr3的晶体结构.结构精修所得的R因子为RP=10.79%,RWP=13.70%,RF=5.99%,RB=8.36%.结果表明,该化合物为六方晶系Ce3MnBi结构类型,空间群为P63/mcm(№.193),点阵参数为a=0.964 60(1)nm,c=0.646 501(7)nm,单位晶胞的化学式数量为Z=2,计算密度为Dx=9.62g/cm3.晶胞中Mn原子占据2b位置,一部分Bi原子占据4d位置,另一部分Bi原子和Pr原子分别占据6g位置.