Crystal structure and magnetic modulation in β−Ce2O2FeSe2

Abstract

Publisher's copyright statement:Reprinted with permission from the American Physical Society: Wang, Chun-Hai, Ainsworth, C. M., Champion, S. D., Stewart, G. A., Worsdale, M. C., Lancaster, T., Blundell, S. J., Brand, Helen E. A. Evans, John S. O. (2017). Crystal structure and magnetic modulation in Ce2O2FeSe2. Physical Review Materials 1(3): 034403 c 2017 by the American Physical Society. Readers may view, browse, and/or download material for temporary copying purposes only, provided these uses are for noncommercial personal purposes. Except as provided by law, this material may not be further reproduced, distributed, transmitted, modi ed, adapted, performed, displayed, published, or sold in whole or part, without prior written permission from the American Physical Society.Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. We report a combination of x-ray and neutron diffraction studies, Mössbauer spectroscopy, and muon spin relaxation (μ + SR) measurements to probe the structure and magnetic properties of the semiconducting β-Ce 2 O 2 FeSe 2 oxychalcogenide. We report a structural description in space group P na2 1 which is consistent with diffraction data and second harmonic generation measurements and reveal an order-disorder transition on one Fe site at T OD ≈ 330 K. Susceptibility measurements, Mössbauer, and μ + SR reveal antiferromagnetic ordering below T N = 86 K and more complex short range order above this temperature. 12 K neutron diffraction data reveal a modulated magnetic structure with q = 0.444b N * .

Antiferromagnetic Semiconductor BaFMn0.5Te with Unique Mn Ordering and Red Photoluminescence

“…For example, the oxypnictides, REOFeAs (RE = rare earth elements), are well-known for their iron-based high- T c ( T c being the superconducting transition temperature) superconductors. − The antiferromagnetism (AFM) in the negative [FeAs] − layers can be suppressed with doping to promote the emergence of unconventional superconductivity, while the positive [REO] + layers influence the T c values. − By substituting the pnictogen with a chalcogen, along with a corresponding substitution of Fe 2+ with Cu + , other analogues in this structure type, REOCuQ (Q = S, Se, Te), have been widely investigated as semiconductors. − Introducing transition metals with +2 valence in these oxychalcogenides leads to a series of REOM 0.5 Se (RE = rare earth elements; M = transition metals) semiconductors. Compounds in this structure type have been shown to host unique and complex modulated structures and magnetic properties. − …”

2D Homologous Series SrFMnBiSn+2 (M = Pb, Ag0.5Bi0.5; n = 0, 1) and Commensurately Modulated Sr2F2Bi2/3S2

“…Two-dimensional (2D) heteroanionic structures contain different anions that segregate into chemically distinct positively and negatively charged layers. They comprise a large number of phases with properties of broad interest in optoelectronics, − thermoelectricity, , superconductivity, − colossal magnetoresistance, and magnetism. − The fundamental properties are determined not only by the chemical compositions and bonds within the layers but also by the interactions between the different slabs. Following hard–soft acid–base theory, the distinct layers form as a result of differences in the electronegativity, ionic radius, and polarizability between the cations and anions, where the soft Lewis acid cations are found in the same layer as the soft Lewis base anions and respectively for the hard Lewis acid cations and hard Lewis base anions .…”

Antiferromagnetic quaternary chalco-halide Ba3(FeS4)I with long Fe⋯Fe distances

“…7–12 For instance, the quasi-2D antiferromagnetic Ln 2 Fe 2 Q 2 O 3 (Ln = Ce, Pr, Nd, Sm; Q = S, Se) 13–18 contains alternately stacked [Ln 2 O 2 ] 2+ and [Fe 2 OS 2 ] 2− SFUs, while the (Li 0.8 Fe 0.2 )OHFeQ (Q = S, Se) 19–21 superconductors feature [(Li 0.8 Fe 0.2 )OH] and [FeQ] SFUs. Moreover, many other Fe-based oxychalcogenides have also been explored, including CaFeQO (Q = S, Se), 22–26 Ca 2 O 3 Fe 2.6 S 2 , 27 Sr 2 Fe 3 Se 2 O 3 , 28,29 A E2 Fe 2 Q 2 O (A E = Sr, Ba; Q = S, Se), 30–32 A E2 F 2 Fe 2 OQ 2 (A E = Sr, Ba; Q = S, Se), 33,34 Ln 2 O 2 FeSe 2 (Ln = La, Ce), 35–38 and so on.…”