LaOsSi3single crystals are synthesized for the first time by an arc melting method.The crystal features a tetragonal BaNiSn3-type structure(space group I4mm) which lacks inversion symmetry along the crystallographic c axis and is isostructural with the intensively studied Rashba-type noncentrosymmetric superconductors LaRhSi3and LaIrSi3.Unlike LaRhSi3and LaIrSi3displaying superconductivity,LaOsSi3shows only metallic behavior over the measured temperature range of 2 K–300 K.The Sommerfeld coefficient γ derived from specific heat is 5.76 mJ·mol-1·K-2,indicating that LaOsSi3has a weak electronic correlation effect.The absence of superconductivity in LaOsSi3may lie in the Os 5d bands in the electronic structure.If it is true,it would be useful to provide complementary knowledge in understanding the relation between conduction and the d bands of M in LaMSi3compounds(M = transition metals).
