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Magnetic order and phase transition in the iron oxysulfide La2O2Fe2OS2

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 نشر من قبل Emma McCabe
 تاريخ النشر 2017
  مجال البحث فيزياء
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The Mott-insulating iron oxychalcogenides exhibit complex magnetic behaviour and we report here a neutron diffraction investigation into the magnetic ordering in La2O2Fe2OS2. This quaternary oxysulfide adopts the anti-Sr2MnO2Sb2-type structure and orders antiferromagnetically below TN = 105 K. We consider both its long-range magnetic structure and its magnetic microstructure, and the onset of magnetic order. It adopts the multi-k vector 2k magnetic structure (k = (0.5 0 0.5) and k = (0 0.5 0.5) and has similarities with related iron oxychalcogenides, illustrating the robust nature of the 2k magnetic structure.

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