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Electronic and magnetic properties of multiferroic ScFeO3

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 نشر من قبل Stephen Lovesey
 تاريخ النشر 2016
  مجال البحث فيزياء
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Experimental techniques using Bragg diffraction may elucidate electronic and magnetic properties of ferric ions in multiferroic ScFeO3 that are puzzling. A collinear magnetic motif of dipole moments is not expected for s-state ions with an acentric parent (paramagnetic) structure, because single-site anisotropy is negligible and antisymmetric exchange interactions promote an inhomogeneous magnetic motif. However, current indications are that ScFeO3 supports G-type antiferromagnetism, with an unknown moment direction, which implies that ferric ions are not in the high-spin 6S state. It is argued that significant insight on these open questions can be achieved by confronting experimental data with calculated structure factors for resonant x-ray and magnetic neutron Bragg spots, and we report results for G-type antiferromagnetism allowed by the corundum-like parent R3c structure. Calculated structure factors include Dirac multipoles that are time-odd and parity-odd, e.g., dipoles that are often called anapoles or toroidal moments.



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