Vacancy ordering in γ-Fe2O3 nanocrystals observed by 57Fe NMR

被引：30

作者：

Bastow, T. J. ^{[1
]}

Trinchi, A. ^{[1
]}

Hill, M. R. ^{[1
]}

Harris, R. ^{[1
]}

Muster, T. H. ^{[1
]}

机构：

[1] CSIRO, Div Engn & Mat Sci, Clayton, Vic 3169, Australia

来源：

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS | 2009年 / 321卷 / 17期

关键词：

Iron oxide; Maghemite; gamma-Fe2O3; Nanoparticle; Nanocrystal; Nuclear magnetic resonance; Solid-state NMR; X-ray diffraction; XRD; MAGNETITE;

D O I：

10.1016/j.jmmm.2009.03.064

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The identification by 57Fe internal field nuclear magnetic resonance (NMR) of hyperfine fields at four Fe sites in the (average) tetragonal unit cell of vacancy-ordered gamma-Fe2O3 (maghemite) is reported. The effects of vacancy redistribution due to annealing the partially vacancy-ordered form has been observed in the Fe-57 lineshape. In addition, the reduction of the particle size of the vacancy-ordered form has been observed to gradually eliminate the vacancy ordering and then to cause a transition from ferrimagnetism to superparamagnetism. Crown Copyright (c) 2009 Published by Elsevier B.V. All rights reserved.

引用

页码：2677 / 2681

页数：5

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