Magnetic and magnetocaloric properties of the high-temperature modification of TbTiGe

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

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

The high-temperature form (HT) of the ternary germanide TbTiGe was prepared by melting. The investigation of HT-TbTiGe by x-ray and neutron powder diffractions shows that the compound crystallizes in the tetragonal CeScSi-type structure (space group I4/mmm; a = 404.84(5) and c = 1530.10(9) pm as unit cell parameters). Magnetization and specific heat measurements as well as neutron powder diffraction performed on HT-TbTiGe reveal a ferromagnet having TC = 300(1) K as the Curie temperature; the Tb-moments are aligned along the c-axis. This magnetic ordering is associated with a modest magnetocaloric effect around room temperature. The isothermal magnetic entropy change ΔSm was determined from the magnetization data; ΔSm reaches, respectively, a maximum value of − 4.3 and − 2.0 J K−1 kg−1 for a magnetic field change of 5 and 2 T.

Mots clés: Magnetism; High pressure; Titanium; Germanium; Terbium

Domaines: Matériaux; Science des matériaux [cond-mat.mtrl-sci]

Sophie Tencé, Etienne Gaudin, Olivier Isnard, Bernard Chevalier. Magnetic and magnetocaloric properties of the high-temperature modification of TbTiGe. Journal of Physics: Condensed Matter, 2012, 24 (29), pp.296002. ⟨10.1088/0953-8984/24/29/296002⟩. ⟨hal-00712605⟩