2013/05/31 by Angel Rodriguez-Fernandez, Stephen W. Lovesey, Stephen William Lovesey +5
Energy · Materials Science · Physics and Astronomy · #Bismuth ferrite #Bragg peak #Bragg's law #Electronic structure #Ferric #Ion #Iron oxide chemistry and applications #Multiferroics #Multiferroics and related materials #X-ray Diffraction in Crystallography #Yield (engineering) #cond-mat.mtrl-sci
paper · pdf · doi:10.7566/jpsj.83.013706
arxiv created 2013/11/14 · openalex publication_date 2013/12/09 · arxiv updated 2013/12/10 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
A new chiral phase of ferric ions in bismuth ferrite, the only material known to support multiferroic behaviour at room temperature, is inferred from extensive sets of data gathered by resonant x-ray Bragg diffraction. Values of all ferric multipoles participating in a minimal model of Fe electronic structure are deduced from azimuthal-angle scans. Extensive sets of azimuthal-angle data, gathered by resonant x-ray Bragg diffraction, yield values of all ferric multipoles participating in a minimal model of Fe electronic structure. Paramagnetic (700 K) and magnetically ordered (300 K) phases of a single crystal of BiFeO3 have been studied with x-rays tuned near to the iron K-edge (7.1135 keV). At both temperatures, intensities at a Bragg spot forbidden in the nominal space-group, R3c, are consistent with a chiral motif of ferric ions in a circular cycloid propagating along (1, 1, 0)H. Templeton and Templeton scattering at 700 K is attributed in part to charge-like quadrupoles in a cycloid. The contribution is not present in a standard, simplified model of electronic states of the resonant ion with trivial cylindrical symmetry.