THE FORMATION OF NONEQUILIBRIUM MICRODOMAINS DURING THE OXIDIATION OF SR2COFEO5

被引:26
作者
BATTLE, PD [1 ]
GIBB, TC [1 ]
NIXON, S [1 ]
机构
[1] UNIV LEEDS,DEPT INORGAN & STRUCT CHEM,LEEDS LS2 9JT,W YORKSHIRE,ENGLAND
关键词
HEAT TREATMENT - Annealing - MAGNETISM - Antiferromagnetism - SPECTROSCOPY; MOSSBAUER - Applications - STRONTIUM COMPOUNDS - Oxidation - X-RAYS - Diffraction;
D O I
10.1016/0022-4596(88)90117-X
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
The phase Sr//2CoFeO//5// plus //y has been studied by Moessbauer spectroscopy, X-ray powder diffraction, and magnetic susceptibility techniques. Quenching in air from 1200 degree C produces a partially oxidized material which contains small nonequilibrium microdomains of the brownmillerite Sr//2CoFeO//5 with excess oxygen accommodated in the domain walls. Quenching in liquid nitrogen from 1200 degree C produces stoichiometric Sr//2CoFeO//5 with a random distribution of cobalt and iron on the tetrahedral and octahedral sites. Annealing under argon at 800 degree C causes preferential occupation of the tetrahedral sites by cobalt. Both the nitrogen-quenched and the annealed sample are antiferromagnetic at room temperature.
引用
收藏
页码:330 / 337
页数:8
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