Anisotropic magnetism and Kondo-lattice behavior in the frustrated antiferromagnet Ce3MgBi5

Abstract

We report the synthesis and physical characterization of single-crystalline Ce3MgBi5, a previously unexplored member of the Ce3MPn5 family. This compound crystallizes in the hexagonal P63/mcm structure, featuring an anisotropic Ce sublattice composed of zig-zag chains along the c axis and a distorted kagome-like network in the basal plane. Magnetization measurements reveal antiferromagnetic order below TN approximately 4.2 K, accompanied by strong magnetic anisotropy and multiple field-induced metamagnetic transitions for fields applied perpendicular to [001], leading to a dome-shaped H-T phase diagram. Electrical transport exhibits characteristic signatures of a Ce-based Kondo lattice, including broad resistivity maxima and pronounced field-dependent anomalies in the magnetoresistance and Hall response that track the magnetic phase boundaries. Specific-heat measurements confirm the magnetic transition and show that the full R ln 2 entropy expected for a Ce3+ Kramers doublet is recovered by 20 K, indicating an extended temperature range of magnetic fluctuations consistent with Kondo correlations. Our results establish Ce3MgBi5 as a platform within the Ce3MPn5 family for exploring the interplay of geometric frustration, magnetic anisotropy, and Kondo-lattice physics under applied magnetic fields.