title: Suppression of magnetic order in Sr3Fe2O4Cl2 by Fe-site substitution by cobalt.
abstract: The low-temperature topotactic reduction of Sr(3)Fe(2-x)Co(x)O(5)Cl(2) oxychloride phases with LiH allows the preparation of phases of composition Sr(3)Fe(2-x)Co(x)O(4)Cl(2) (0 ≤ x ≤ 1). The reduced phases adopt body-centered tetragonal structures which are isostructural with Sr(3)Fe(2)O(4)Cl(2) and contain square-planar (Fe/Co)O(4) centers connected into apex-linked sheets, analogous to the CuO(2) sheets present in superconducting cuprate phases. As the cobalt concentration in Sr(3)Fe(2-x)Co(x)O(4)Cl(2) is increased the antiferromagnetic order of the Sr(3)Fe(2)O(4)Cl(2) host phase is suppressed, ultimately leading to spin-glass behavior, at low temperature, in Sr(3)Fe(2-x)Co(x)O(4)Cl(2) phases with x ≥ 0.8. The limited influence of cobalt substitution on the reactions which form the Sr(3)Fe(2-x)Co(x)O(4)Cl(2) phases is discussed and contrasted to that of the related SrFeO(3-δ)-SrFeO(2) system.
authors.affiliation: Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom.
authors.forename: Edward
authors.initials: E
authors.lastname: Dixon
authors.forename: Michael A
authors.initials: MA
authors.lastname: Hayward