Charge order and three-site distortions in the Verwey structure of magnetite

@article{Senn2012ChargeOA,
  title={Charge order and three-site distortions in the Verwey structure of magnetite},
  author={Mark S. Senn and Jon P. Wright and John Paul Attfield},
  journal={Nature},
  year={2012},
  volume={481},
  pages={173-176}
}
The mineral magnetite (Fe3O4) undergoes a complex structural distortion and becomes electrically insulating at temperatures less than 125 kelvin. Verwey proposed in 1939 that this transition is driven by a charge ordering of Fe2+ and Fe3+ ions, but the ground state of the low-temperature phase has remained contentious because twinning of crystal domains hampers diffraction studies of the structure. Recent powder diffraction refinements and resonant X-ray studies have led to proposals of a… 
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Jahn-Teller distortion driven magnetic polarons in magnetite
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TLDR
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A mechanism of the Verwey transition in magnetite $({\mathrm{Fe}}_{3}{\mathrm{O}}_{4}),$ which has been argued to be a charge ordering transition so far, is proposed. Based on mean-field calculations
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