MS Senn, JP Wright, JP Attfield, Nature 481 (2012), 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 phaseRead more