Anisotropic long-range interactions in NdCu2

A consistent model for the magnetic interactions in the orthorhombic interm etallic NdCu2 is based on the determination of the magnetic phases and the analysis of the magnetic excitations. The strong anisotropy of the magnetic interactions is evident from a comparison of static and dynamic properties of the system. In particular, we can show by a model calculation, that the stability of the magnetic phases, which have been observed by neutron scat tering experiments in different magnetic fields implies a non-negligible in teraction between distant Nd ions (i.e. about - 0.54 mu eV at 2.6 nm distan ce). (C) 2000 Elsevier Science B.V. AII rights reserved.