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The compound DyNi2Mn with a MgCu2-type structure was synthesized, even though the atom ratio of Dy to transition metal was confirmed to be 1:3, by using the energy dispersive spectrum method. The X-ray diffraction pattern (XRD) could be well indexed with a cubic Laves cell with the lattice parameter a = 7.1406(2) Angstrom and space group Fd3m. The refinement result of the XRD pattern indicates that 73.8% of the 8a sites (Dy sites) are occupied by Dy atoms, 21.4% by Mn atoms, and 4.8% are empty. The compound shows ferrimagnetic coupling of the Dy and Mn moments with an ordering temperature T-C of 94 K. The spontaneous magnetization at 5 K is 6.7mu(B)/f.u. A large coercive field of 0.73 T at 5 K is found for the bulk sample, which can be understood in terms of narrow-domain-wall pinning. (C) 2002 Elsevier Science Ltd. All rights reserved.