Charge order in LuFe2O4: an unlikely route to ferroelectricity.
نویسندگان
چکیده
We present the refinement of the crystal structure of charge-ordered LuFe2O4, based on single-crystal x-ray diffraction data. The arrangement of the different Fe-valence states, determined with bond-valence-sum analysis, corresponds to a stacking of charged Fe bilayers, in contrast with the polar bilayers previously suggested. This arrangement is supported by an analysis of x-ray magnetic circular dichroism spectra, which also evidences a strong charge-spin coupling. The nonpolar bilayers are inconsistent with charge order based ferroelectricity.
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ورودعنوان ژورنال:
- Physical review letters
دوره 108 18 شماره
صفحات -
تاریخ انتشار 2012