title: SrFe0.5Ru0.5O2: square-planar Ru2+ in an extended oxide.
abstract: Low-temperature topochemical reduction of the cation disordered perovskite phase SrFe(0.5)Ru(0.5)O(3) with CaH(2) yields the infinite layer phase SrFe(0.5)Ru(0.5)O(2). Thermogravimetric and X-ray absorption data confirm the transition metal oxidation states as SrFe(0.5)(2+)Ru(0.5)(2+)O(2); thus, the title phase is the first reported observation of Ru(2+) centers in an extended oxide phase. DFT calculations reveal that, while the square-planar Fe(2+) centers adopt a high-spin S = 2 electronic configuration, the square-planar Ru(2+) cations have an intermediate S = 1 configuration. This combination of S = 2, Fe(2+) and S = 1, Ru(2+) is consistent with the observed spin-glass magnetic behavior of SrFe(0.5)Ru(0.5)O(2).
authors: Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom.
authors: Fabio
authors: F
authors: Denis Romero
authors: Steven J
authors: SJ
authors: Burr
authors: John E
authors: JE
authors: McGrady
authors: Diego
authors: D
authors: Gianolio
authors: Giannantonio
authors: G
authors: Cibin
authors: Michael A
authors: MA
authors: Hayward