Magnetocaloric effect and transport properties of Gd5Ge2(Si1−Sn )2 (x=0.23 and 0.40) compounds

Abstract We report a study about the structural properties of polycrystalline samples of nominal composition Gd 5 Ge 2 (Si 1− x Sn x ) 2 ( x =0.23, 0.40) that closely influence their physical behavior particularly related to electric resistivity and magnetocaloric (MCE) effect. The samples were characterized by X-ray diffraction (XRD) using the Rietveld refinement method, metallographic analyses, 119 Sn Mossbauer spectroscopy, DC magnetization and electrical transport measurements. It was identified a Gd 5 Si 2 Ge 2 -monoclinic phase for x =0.23 and a Sm 5 Sn 4 -orthorhombic phase (type II) for x =0.40, both with two non-equivalent crystallographic sites for the Sn ions. We were able to infer on the role of tin on the magnetic and transport properties in these compounds.