Magnetic ordering in Tm5Ni2In4

Physical properties of the Tm5Ni2In4 compound have been investigated by means of magnetometric, calorimetric as well as neutron diffraction measurements. The compound crystallizes in the orthorhombic Lu5Ni2In4-type crystal structure (space group Pbam, No. 55). The reported results indicate that the sample exhibits an antiferromagnetic ordering below TN = 4.1 K. The Tm3+ ions occupy three crystal positions within unit cell: one 2a site and two 4g sites. Analysis of neutron diffraction data collected at T = 1.5 K, together with group theory symmetry analysis predictions show that Tm magnetic moments form a non-collinear magnetic structure described by the propagation vector k = [0, ½, ½]. The magnetic moments lie in the (0 0 1) plane.