Journal article
Pressure tuning of charge ordering in iron oxide
University of Bayreuth1
German Electron Synchrotron2
Indian Institute of Technology Tirupati3
University of Augsburg4
The European Synchrotron5
Department of Physics, Technical University of Denmark6
Neutrons and X-rays for Materials Physics, Department of Physics, Technical University of Denmark7
A Verwey-type charge-ordering transition in magnetite at 120 K leads to the formation of linear units of three iron ions with one shared electron, called trimerons. The recently-discovered iron pentoxide (Fe4O5) comprising mixed-valent iron cations at octahedral chains, demonstrates another unusual charge-ordering transition at 150 K involving competing formation of iron trimerons and dimerons.
Here, we experimentally show that applied pressure can tune the charge-ordering pattern in Fe4O5 and strongly affect the ordering temperature. We report two charge-ordered phases, the first of which may comprise both dimeron and trimeron units, whereas, the second exhibits an overall dimerization involving both the octahedral and trigonal-prismatic chains of iron in the crystal structure.
We link the dramatic change in the charge-ordering pattern in the second phase to redistribution of electrons between the octahedral and prismatic iron chains, and propose that the average oxidation state of the iron cations can pre-determine a charge-ordering pattern.
Language: | English |
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Publisher: | Nature Publishing Group UK |
Year: | 2018 |
Pages: | 4142 |
ISSN: | 20411723 |
Types: | Journal article |
DOI: | 10.1038/s41467-018-06457-x |
ORCIDs: | 0000-0003-1027-0998 , 0000-0003-0248-1728 , 0000-0001-8652-024X , 0000-0003-3285-445X , 0000-0002-5618-3219 , 0000-0002-0755-0422 , 0000-0001-5680-9106 and Kantor, Innokenty |