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

We report a study about the structural properties of polycrystalline samples of nominal composition Gd5Ge2(Si1-xSnx)2 (x=0.2,0.40) 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, 119Sn Mossbauer spectroscopy, DC magnetization and electrical transport measurements. It was identified a Gd5Si2Ge2-monoclinic phase for x=0.23 and a Sm5Sn4-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.