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arXiv · 1709.03323

Magnetic order and phase transition in the iron oxysulfide La2O2Fe2OS2

Reeya K. Oogarah·Emmanuelle Suard·Emma E. McCabe
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Abstract

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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Reeya K. Oogarah, Emmanuelle Suard, Emma E. McCabe. 2017-09-11. Magnetic order and phase transition in the iron oxysulfide La2O2Fe2OS2. https://doi.org/10.1016/j.jmmm.2017.09.024

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