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Orthorhombic versus monoclinic symmetry of the charge-ordered state of NaV2O5

Sander van Smaalen·Peter Daniels·Lukas Palatinus·Reinhard K. Kremer
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Abstract

High-resolution X-ray diffraction data show that the low-temperature superstructure of alpha-NaV2O5 has an F-centered orthorhombic 2a x 2b x 4c superlattice. A structure model is proposed, that is characterized by layers with zigzag charge order on all ladders and stacking disorder, such that the averaged structure has space group Fmm2. This model is in accordance with both X-ray scattering and NMR data. Variations in the stacking order and disorder offer an explanation for the recently observed devils staircase of the superlattice period along c.

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Sander van Smaalen, Peter Daniels, Lukas Palatinus, Reinhard K. Kremer. 2001-08-24. Orthorhombic versus monoclinic symmetry of the charge-ordered state of NaV2O5. https://doi.org/10.1103/physrevb.65.060101

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