DETERMINATION OF COORDINATION NUMBERS AND OXIDATION-STATES IN CHROMIUM OXIDES BY EXTENDED X-RAY ABSORPTION FINE-STRUCTURE SPECTROSCOPY

被引：9

作者：

GIBB, TC

机构：

[1] School of Chemistry, The University

来源：

JOURNAL OF MATERIALS CHEMISTRY | 1992年 / 2卷 / 01期

关键词：

EXAFS SPECTROSCOPY; XANES SPECTROSCOPY; DEFECT ORDERING; CHROMIUM;

D O I：

10.1039/jm9920200057

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Chromium and iron K-edge extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) measurements for several phases in the Sr2Cr(x)Fe(2-x)O5+y system have established that there are substantial numbers of chromium atoms with either short (ca. 1.65 angstrom) or long (ca. 1.91 angstrom) distances to oxygen. These can be attributed to high oxidation states of chromium in tetrahedral co-ordination and Cr3+ ions in octahedral co-ordination, respectively. There is also some evidence for chromium in edge-sharing polyhedra, but not in face-sharing polyhedra, while the iron is in corner-sharing polyhedra. Possible model structures for the 15R phase are discussed.

引用

页码：57 / 64

页数：8

共 21 条

[1] AN INVESTIGATION OF NON-STOICHEIOMETRY IN THE SYSTEMS SRFEO3-Y AND SRCOO3-Y BY IRON AND COBALT K-EDGE EXTENDED X-RAY ABSORPTION FINE-STRUCTURE SPECTROSCOPY [J].