MEM-based structure-refinement system REMEDY and its applications

被引：79

作者：

Izumi, F

Kumazawa, S

Ikeda, T

Hu, WZ

Yamamoto, A

Oikawa, K

机构：

[1] Natl Inst Res Inorgan Mat, Tsukuba, Ibaraki 3050044, Japan

[2] KEK, Inst Mat Struct Sci, Tsukuba, Ibaraki 3050801, Japan

[3] Superconduct Res Lab, Koto Ku, Tokyo 1350062, Japan

[4] Tokyo Univ Mercantile Marine, Koto Ku, Tokyo 1358533, Japan

[5] JAERI, Adv Sci Res Ctr, Tokai, Ibaraki 3191195, Japan

来源：

EPDIC 7: EUROPEAN POWDER DIFFRACTION, PTS 1 AND 2 | 2001年 / 378-3卷

关键词：

electron density; layered compound; maximum-entropy method; nuclear density; superconductor; whole-pattern fitting; zeolite;

D O I：

10.4028/www.scientific.net/MSF.378-381.59

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

A Rietveld-analysis program RIETAN was combined with MEED for a maximum-entropy method (MEM) to grow into an integrated software REMEDY. At first, 'observed' structure factors, F-o, estimated after Rietveld analysis are analyzed by the MEM to give electron/nuclear densities biased by a structural model. Then, we evaluate structure factors, (FeMEM)-M-(), by the Fourier transform of the densities and fit the whole powder pattern calculated from the F-e(MEM) data to the observed one to refine parameters irrelevant to the structure. F-o data obtained in such a manner are analyzed again by the MEM. MEM analysis and whole-pattern fitting are alternately repeated until R factors in the pattern fitting no longer decrease. REMEDY was utilized to investigate (a) positional disorder of K+ ions interlayered in KxTi2-x/3Li(x)/O-3(4), (b) atomic arrangement of K clusters in K-type LTA, and (c) nuclear/electron-density distribution in HgBa2CUO4+delta.

引用

页码：59 / 64

页数：6

共 18 条

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