ThIrSn: A noncentrosymmetric intermetallic with a distorted kagome structure

We report a comprehensive study of the ternary compound ThIrSn, characterized by a distorted kagome lattice of Th atoms in polycrystalline form. The compound adopts a noncentrosymmetric ZrNiAl-type crystal structure, with cell parameters a=b=7.5097(4)0.16em0ex and c=4.1042(3)0.16em0ex. The resistivity and magnetic susceptibility measurements reveal that ThIrSn exhibits metallic behavior, low magnetoresistance, and paramagnetic characteristics. Hall effect measurements have determined that the carrier type is predominantly electrons, following a single-band model. Furthermore, first-principles calculations indicate that the electronic states near the Fermi level are predominantly contributed by Th and Ir. The band structure exhibits Dirac-like crossings and van Hove singularities at the M and K points, suggesting the potential existence of nontrivial topological characteristics. This work not only establishes ThIrSn as a promising platform for investigating potential topological metals, but also advances the study of ternary intermetallic compounds in distorted kagome lattice systems.