Completing the triad: synthesis, structure and magnetic properties of kagome metals Ti3Mn3Sn4Ga and Hf3Mn3Sn4Ga

Abstract

Single crystals of Mn-based kagome metals Ti₃Mn₃Sn₄Ga and Hf₃Mn₃Sn₄Ga were grown from Sn flux. The X-ray structural analysis showed that the two compounds are isostructural to recently reported Zr₃Mn₃Sn₄Ga and feature a kagome lattice of Mn linear chains linked by Sn atoms. The structural analysis also revealed noticeable changes in the interatomic distances, primarily T-Sn ones, originating from differences in atomic radii of T = Ti, Zr, and Hf. Ti₃Mn₃Sn₄Ga and Hf₃Mn₃Sn₄Ga order magnetically at 110 K and 160 K, respectively, which is higher than that reported for Zr₃Mn₃Sn₄Ga. While Hf₃Mn₃Sn₄Ga demonstrates antiferromagnetic ordering below the transition temperature, Ti₃Mn₃Sn₄Ga displays small uncompensated moment directed along the c axis (0.02 μ_B/Mn at 2 K), which exhibits several characteristic features of a spin-glass state, including sensitivity to the magnetic history of a sample and a pronounced shift of the magnetic hysteresis if cooled with the field.