Static bismuth disorder in Bi2-x(CrTa)O7-y

被引：29

作者：

Ismunandar

Kamiyama, T

Oikawa, K

Hoshikawa, A

Kennedy, BJ ^{[1
]}

Kubota, Y

Kato, K

机构：

[1] High Energy Accelerator Res Org, Inst Mat Struct Sci, Tsukuba, Ibaraki 3050801, Japan

[2] Inst Teknol Bandung, Dept Kimia, Bandung 40132, Indonesia

[3] Univ Sydney, Sch Chem, Ctr Heavy Metals Res, Sydney, NSW 2006, Australia

[4] Osaka Womens Univ, Fac Sci, Dept Environm Sci, Sakai, Osaka 5900035, Japan

[5] Japan Synchrotron Radiat Res Inst, Mikazuki, Hyogo 6795198, Japan

来源：

MATERIALS RESEARCH BULLETIN | 2004年 / 39卷 / 4-5期

基金：

澳大利亚研究理事会;

关键词：

oxides; neutron scattering; X-ray diffraction; crystal structure;

D O I：

10.1016/j.materresbull.2003.12.017

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The crystal structure of the pyrochlore Bi2-x(CrTa)O7-y has been refined by the Rietveld method from powder neutron and synchrotron X-ray diffraction data. Using the ideal pyrochlore structural model, anomalously high atomic displacement parameters (APD), which could not be satisfactorily explained with anisotropic ADP, of both Bi and O' sites were observed. The structure was successfully refined with a model that incorporated static displacive disorder of both the Bi and O' atoms. Using this model physically reasonable ADP parameters for both the Bi and O' atoms, and improvement in the various measure of fit were obtained. The underbonding of the Bi atoms, observed in ideal pyrochlore model, but removed in the disordered structure, is believed to be the main driving force for this disorder. (C) 2004 Elsevier Ltd. All rights reserved.

引用

页码：553 / 560

页数：8

共 17 条

[1] Static disorder from lone-pair electrons in Bi2-xMxRu2O7-y (M=Cu, Co; x=0, 0.4) pyrochlores [J].