Publication
Title
Charge-ordering transition in iron oxide $Fe_{4}O_{5}$ involving competing dimer and trimer formation
Author
Abstract
 Phase transitions that occur in materials, driven, for instance, by changes in temperature or pressure, can dramatically change the materials' properties. Discovering new types of transitions and understanding their mechanisms is important not only from a fundamental perspective, but also for practical applications. Here we investigate a recently discovered Fe4O5 that adopts an orthorhombic CaFe3O5-type crystal structure that features linear chains of Fe ions. On cooling below similar to 150 K, Fe4O5 undergoes an unusual charge-ordering transition that involves competing dimeric and trimeric ordering within the chains of Fe ions. This transition is concurrent with a significant increase in electrical resistivity. Magnetic-susceptibility measurements and neutron diffraction establish the formation of a collinear antiferromagnetic order above room temperature and a spin canting at 85 K that gives rise to spontaneous magnetization. We discuss possible mechanisms of this transition and compare it with the trimeronic charge ordering observed in magnetite below the Verwey transition temperature.
Language
English
Source (journal)
Nature chemistry
Publication
2016
ISSN
1755-4330
1755-4349
Volume/pages
8:5(2016), p. 501-508
ISI
000374534100019
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
 Faculty/Department Research group [E?say:metaLocaldata.cgzprojectinf] ESTEEM 2 - Enabling science and technology through European electron microscopy.IFOX - Interfacing Oxides.Revealing the source of emergent properties in complex oxides via direct imaging of charge/orbital/spin ordering. Publication type Subject Affiliation Publications with a UAntwerp address