单斜镁星叶石的晶体结构再测定

DETERMINE OF MONOCLINIC ASTROPHYLLITE CRYSTAL STRUCTURE

通过四圆单晶衍射仪收集衍射数据，精确测定了单斜镁星叶石的晶体结构，其Ｒ因子为０．０６１，确定空间群为Ａ２，Ｔｉ的配位数为５，Ｎａ有两种结晶学位置，一种是呈八次配位位于结构层间，另一种是六次配位位于阳离子八面体层中，使单斜镁星叶石成为大阳离子层状硅酸盐。最终晶体化学式为Ｋ２ＮａＮａ（Ｆｅ，Ｍｎ）４Ｍｇ２Ｔｉ２［Ｓｉ４Ｏ１２］２（ＯＨ）４（ＯＨ，Ｆ）２。

The structure of monoclinic astrophyllite was determined by instensity data were collected on Rigaku PASA IIs four circle diffractometer.The final R=0.061,space group is A2,The determinetion indicated that the coordination typies,their coordination numbers are eight and six,its formula is K 2NaNa(Fe,Mn) 4Mg 2Ti 2[Si 4O 12 ] 2(OH) 4(OH,F) 2,Z=2.