Magnetic structure and thermodynamic properties of TmPtIn

Physical properties of TmPtIn have been investigated by means of magnetic, electrical transport, calorimetric as well as neutron diffraction measurements. The compound crystallizes in the hexagonal ZrNiAl-type crystal structure. It orders antiferromagnetically below TN = 3.5 K with the Tm magnetic moments confined to the basal hexagonal plane. They form a non-collinear “triangular” magnetic structure that may be described by the propagation vector k⇒=[14,14,12]. At 1.6 K, the Tm magnetic moment is equal to 5.59(9)μB5.59(9)μB. The antiferromagnetic character of the electronic ground state is reflected in the low temperature behaviors of the magnetic susceptibility and the specific heat, which may be described by spin-wave theory of antiferromagnetic magnons with linear dispersion relation. The compound exhibits metallic character of electrical conduction.