Abstract

The two B-site ions Mn3+ and Mn4+ in the stoichiometric spinel structure LiMn2O4 form a complex, columnar ordered pattern below the charge-ordering transition at room temperature. On further cooling to below 66 K, the system develops long-range antiferromagnetic order. In contrast, whereas lithium-substituted Li[Mn2−xLix]O4 also undergoes a charge-ordering transition around room temperature, it only displays frozen in short-range magnetic order below ~25-30 K. We investigate to what extent the columnar charge-order pattern observed in LiMn2O4 can account for the measured magnetic ordering patterns in both the pure and Li-substituted (x=0.04) compounds. We conclude that eightfold rings of Mn4+ ions form the main magnetic unit in both compounds (x=0,0.04), and that clusters formed out of these rings act as superspins in the doped compound.

Department(s)

Physics

Sponsor(s)

United States. Department of Energy

Keywords and Phrases

Antiferromagnetic Materials; Lithium Compounds; Long-Range Order; Magnetic Structure; Short-Range Order

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2009 American Institute of Physics (AIP), All rights reserved.

Included in

Physics Commons

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