The new ternary silicide Gd₅CoSi₂: Structural, magnetic and magnetocaloric properties

Charlotte Mayer (1) , Etienne Gaudin (1) , Stéphane Gorsse (1) , Bernard Chevalier (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

Gd₅CoSi₂ was prepared by annealing at 1003 K. Its investigation by the X-ray powder diffraction shows that the ternary silicide crystallizes in a tetragonal structure deriving from the Cr₅B₃-type (I4/mcm space group; a=7.5799(4) and c=13.5091(12) Å as unit cell parameters). The Rietveld refinement shows a mixed occupancy on the (8h) site between Si and Co atoms. Magnetization and specific heat measurements performed on Gd₅CoSi₂ reveal a ferromagnetic behaviour below T_C=168 K. This magnetic ordering is associated to an interesting magnetocaloric effect; the adiabatic temperature change ΔT_ad is about 3.1 and 5.9 K, respectively, for a magnetic field change of 2 and 4.6 T.

Domaines: Matériaux

Charlotte Mayer, Etienne Gaudin, Stéphane Gorsse, Bernard Chevalier. The new ternary silicide Gd₅CoSi₂: Structural, magnetic and magnetocaloric properties. Journal of Solid State Chemistry, 2011, 184 (2), pp.325-330. ⟨10.1016/j.jssc.2010.11.023⟩. ⟨hal-00565319⟩