THE ELECTRON-DISTRIBUTION IN CORUNDUM - A STUDY OF THE UTILITY OF MERGING SINGLE-CRYSTAL AND POWDER DIFFRACTION DATA

被引:38
作者
BROWN, AS [1 ]
SPACKMAN, MA [1 ]
HILL, RJ [1 ]
机构
[1] CSIRO,DIV MINERAL PROD,PORT MELBOURNE,VIC 3207,AUSTRALIA
来源
ACTA CRYSTALLOGRAPHICA SECTION A | 1993年 / 49卷
关键词
D O I
10.1107/S0108767392011267
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Powder X-ray diffraction data for corundum were collected by a variety of methods and reduced to structure amplitudes by two profile-fitting techniques. The resulting averaged powder-data set was merged with three different single-crystal data sets to assess the improvements possible over least-squares modelling of extinction for accurate electron density analysis of minerals. With reference to the deformation electron density derived from multipole refinements, it is concluded that this strategy offers advantages over the post facto modelling of severe extinction effects commonly observed in such systems. The deformation electron density is found to be in quantitative agreement with the results of recent ab initio calculations on clusters and the bulk.
引用
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页码:513 / 527
页数:15
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