Magnetic structure of the quasi-two-dimensional compound CoTa2O6

E.J. Kinast (1) , C.A. dos Santos (2) , D. Schmitt (3) , Olivier Isnard (4) , M.A. Gusmao (2) , J.M.B. da Cunha (2)

1 Universidade Estadual do Rio Grande do Sul
2 Instituto de Física
3 LGIT - Laboratoire de Géophysique Interne et Tectonophysique
4 NEEL - MRS - Matériaux, Rayonnements, Structure

We report on a detailed investigation of magnetic properties of CoTa2O6 using several techniques: neutron and X-ray diffraction, specific-heat, magnetic susceptibility, and magnetization measurements. The compound shows quasi-two-dimensional behavior due to its layered structure of alternating Co-O and Ta-O planes. We find that all magnetic moments lie entirely in the Co-O planes, along easy axes determined by the orientations of oxygen octahedra that surround the Co ions. The easy axes in successive magnetic planes have relative orientations that differ by 90°. Antiferromagnetic ordering is observed below 6.6 K, with propagation vectors (±1/4,1/4,1/4) associated to the two non-equivalent sets of Co2+ ions, whose magnetic moments are perpendicularly oriented.

Keywords: Two-dimensional magnetism; Trirutile; Neutron diffraction

Domains: Geomorphology

E.J. Kinast, C.A. dos Santos, D. Schmitt, Olivier Isnard, M.A. Gusmao, et al.. Magnetic structure of the quasi-two-dimensional compound CoTa2O6. Journal of Alloys and Compounds, 2010, 491 (1-2), pp.41-44. ⟨10.1016/j.jallcom.2009.10.241|⟩. ⟨insu-00650992⟩