Crystal Growth and Physical Properties of Hybrid CoSn–YCo₆Ge₆ Structure Type Ln_xCo₃(Ge_1–ySn_y)₃ (Ln = Y, Gd)

Abstract

There is an ongoing interest in kagome materials because they offer tunable platforms at the intersection of magnetism and electron correlation. Herein, we examine single crystals of new kagome materials, Ln x Co 3 (Ge 1−y Sn y ) 3 (Ln = Y, Gd; y = 0.11, 0.133), which were produced using the Sn flux-growth method. Unlike many of the related chemical analogues with the LnM 6 X 6 formula (M = transition metal and X = Ge, Sn), the Y and Gd analogues crystallize in a hybrid YCo 6 Ge 6 /CoSn structure, with Sn substitution. While the Y analogue displays temperatureindependent paramagnetism, magnetic measurements of the Gd analogue reveal a magnetic moment of 8.48 μ B , indicating a contribution from both Gd and Co. Through anisotropic magnetic measurements, the direction of Co-magnetism can be inferred to be in plane with the kagome net, as the Co contribution is only along H//a. Crystal growth and structure determination of Y x Co 3 (Ge,Sn) 3 and Gd x Co 3 (Ge,Sn) 3 , two new hybrid kagome materials of the CoSn and YCo 6 Ge 6 structure types. Magnetic properties, heat capacity, and resistivity on single crystals are reported.