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arXiv · 0707.2743

Charge Order Superstructure with Integer Iron Valence in Fe2OBO3

M. Angst·P. Khalifah·R. P. Hermann·H. J. Xiang·M. -H. Whangbo·V. Varadarajan·J. W. Brill·B. C. Sales·D. Mandrus
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Abstract

Solution-grown single crystals of Fe2OBO3 were characterized by specific heat, Mossbauer spectroscopy, and x-ray diffraction. A peak in the specific heat at 340 K indicates the onset of charge order. Evidence for a doubling of the unit cell at low temperature is presented. Combining structural refinement of diffraction data and Mossbauer spectra, domains with diagonal charge order are established. Bond-valence-sum analysis indicates integer valence states of the Fe ions in the charge ordered phase, suggesting Fe2OBO3 is the clearest example of ionic charge order so far.

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M. Angst, P. Khalifah, R. P. Hermann, H. J. Xiang, M. -H. Whangbo, V. Varadarajan, J. W. Brill, B. C. Sales, D. Mandrus. 2007-07-18. Charge Order Superstructure with Integer Iron Valence in Fe2OBO3. https://doi.org/10.1103/physrevlett.99.086403

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