Jump to main content
Jump to site search


Synthesis and magnetic characterisation of Fe1−xMgxSb2O4 (x = 0.25, 0.50, 0.75) and their oxygen-excess derivatives, Fe1−xMgxSb2O4+y

Author affiliations

Abstract

Three new materials of composition Fe1−xMgxSb2O4 (x = 0.25, 0.50, 0.75) with the tetragonal schafarzikite structure have been synthesised. Magnetic susceptibility measurements suggest that Fe1−xMgxSb2O4 (x = 0.25, 0.50) are canted antiferromagnets whilst Fe0.25Mg0.75Sb2O4 is paramagnetic. The magnetic ordering temperatures decrease as the Mg2+ concentration increases. The materials form oxygen-excess phases when heated in oxygen-rich atmospheres at temperatures of ∼350 °C. 57Fe Mössbauer spectroscopy shows that the oxidation process involves the oxidation of Fe2+ to Fe3+. Powder neutron diffraction confirms the location of the excess oxygen within the structural channels and reveals a change in magnetic order at low temperatures from A-type (magnetic moments along 〈100〉) for Fe1−xMgxSb2O4 to C-type (magnetic moments along [001]) for the oxidised materials. The change is attributed to a weakening of the antiferromagnetic exchange interactions between edge-linked FeO6 octahedra for the Fe3+-containing materials.

Graphical abstract: Synthesis and magnetic characterisation of Fe1−xMgxSb2O4 (x = 0.25, 0.50, 0.75) and their oxygen-excess derivatives, Fe1−xMgxSb2O4+y

Back to tab navigation
Please wait while Download options loads

Publication details

The article was received on 24 Mar 2017, accepted on 02 May 2017 and first published on 05 May 2017


Article type: Paper
DOI: 10.1039/C7TC01256J
Citation: J. Mater. Chem. C, 2017, Advance Article
  •   Request permissions

    Synthesis and magnetic characterisation of Fe1−xMgxSb2O4 (x = 0.25, 0.50, 0.75) and their oxygen-excess derivatives, Fe1−xMgxSb2O4+y

    B. P. de Laune, M. J. Whitaker, J. F. Marco, M. F. Thomas, F. J. Berry, M. R. Lees and C. Greaves, J. Mater. Chem. C, 2017, Advance Article , DOI: 10.1039/C7TC01256J

Search articles by author