Synthesis and magnetic properties of the ternary germanide TbScGe

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.

► The magnetocaloric properties of the ternary germanide TbScGe were investigated. ► The compound was characterized by microprobe analysis, X-ray powder diffraction, magnetization and specific heat measurements. ► TbScGe is a ferromagnet showing a moderate magnetocaloric effect at 250 K.