Eur. Phys. J. B 52, 371-376 (2006)
https://doi.org/10.1140/epjb/e2006-00316-5

Neutron diffraction study of the magnetic structure of Na₂RuO₄

¹ Max Planck Institute for Solid State Research, Stuttgart, Germany
² Laboratory for Neutron Scattering, ETH Zürich & Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
³ Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland

Corresponding author: ^a M.Jansen@fkf.mpg.de

Received: 12 April 2006
Published online: 7 August 2006

Abstract

Nuclear and magnetic structures of sodium ruthenate (VI) have been studied by neutron powder diffraction in the temperature range 1.5–200 K. Na₂RuO₄ crystallizes in the monoclinic structure, with space group P 2₁/c. The structure consists of apical corner sharing RuO₅ trigonal bipyramids forming infinite chains running along the b axis. These infinite [ RuO₃O_2/2] chains form a pseudo hexagonal close packing of rods with Ru–Ru distances of 3.51 Å within the chains and 5.30–5.47 Å between the chains. At T_N=37.2 K a magnetic transition leads to an antiferromagnetic state. The Ru⁶⁺ magnetic moments are ordered antiferromagnetically along the chains (b-axis), while the inter-chain interaction is ferromagnetic. A classical infinite chain model was fitted to the magnetic susceptibility data in order to estimate the strength of the nearest-neighbor exchange interactions along and between the chains, resulting in an intrachain coupling parameter of 2J=-86 K, and an interchain parameter J_⊥ with 2J_⊥ = 3 K.