Synthesis and magnetic properties of the ternary germanide TbScGe

Sophie Tencé (1) , Olivier Isnard (2) , Etienne Gaudin (1) , Bernard Chevalier (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 NEEL - MRS - Matériaux, Rayonnements, Structure

TbScGe is obtained as pure phase after melting of the constituents followed by an annealing at 1173 K. Contrary to what was suggested previously, this ternary germanide does not present a high temperature form with the hexagonal Ti5Ga4-type structure after melting and quenching; the as quenched sample is a mixture based on the two solid solutions (Tb1−xScx)5Ge3 and Tb1−xScx. TbScGe adopts the tetragonal CeScSi-type structure with a = 4.219 and c = 15.452 Å as unit cell parameters. Its investigation by magnetization and specific heat measurements reveals a ferromagnetic behavior below TC = 250 K inducing a moderate magnetocaloric effect; for a magnetic field change of 2 T, the magnetic entropy change ΔSm is equal to −1.6 J K−1 kg−1 which corresponds to an adiabatic temperature change ΔTad of 1.25 K.

Mots clés: Structural properties; Synthesis; Ternary germanide; Ferromagnetism; Magnetocaloric properties

Domaines: Matériaux

Sophie Tencé, Olivier Isnard, Etienne Gaudin, Bernard Chevalier. Synthesis and magnetic properties of the ternary germanide TbScGe. Journal of Alloys and Compounds, 2013, 560, pp.195-199. ⟨10.1016/j.jallcom.2013.02.002⟩. ⟨hal-00797634⟩