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arXiv · 0811.3350

A critical re-examination of resonant soft x-ray Bragg forbidden reflections in magnetite

S. B. Wilkins·S. Di Matteo·T. A. W. Beale·Y. Joly·C. Mazzoli·P. D. Hatton·P. Bencok·F. Yakhou·V. A. M. Brabers
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Abstract

Magnetite, Fe$_3$O$_4$, displays a highly complex low temperature crystal structure that may be charge and orbitally ordered. Many of the recent experimental claims of such ordering rely on resonant soft x-ray diffraction at the oxygen K and iron L edges. We have re-examined this system and undertaken soft x-ray diffraction experiments on a high-quality single crystal. Contrary to previous claims in the literature, we show that the intensity observed at the Bragg forbidden (001/2)$_c$ reflection can be explained purely in terms of the low-temperature structural displacements around the resonant atoms. This does not necessarily mean that magnetite is not charge or orbitally ordered, but rather that the present sensitivity of resonant soft x-ray experiments does not allow conclusive demonstration of such ordering.

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S. B. Wilkins, S. Di Matteo, T. A. W. Beale, Y. Joly, C. Mazzoli, P. D. Hatton, P. Bencok, F. Yakhou, V. A. M. Brabers. 2008-12-03. A critical re-examination of resonant soft x-ray Bragg forbidden reflections in magnetite. https://doi.org/10.1103/physrevb.79.201102

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