Exchange Interactions in Rare Earth Metals


    The complex magnetic orderings observed in the rare earth metals may be understood phenomenologically(i) in terms of an effective exchange interaction J(R) between the localised 4f electrons a distance R apart which is of long range so that the Fourier transform J(a) = J(,R)e' R has a maximum for _ at some general point in the Brillouin Zone. The anisotropy of the systems can be understood in terms of the crystalline electric field which influences the orbital motion of the f electrons. In the second half of the rare earth series the crystal field effects are comparable t6 the exchange energy, in the first half they are somewhat larger. The detailed form of J(R) and of the anisotropy terms can be studied through the spin-wave spectra which are verd complex in these complicated magnetic structures(.) The details of the magnetic ordering are found by neutron diffraction to change with temperature T

    Cite this paper

    @inproceedings{ExchangeII, title={Exchange Interactions in Rare Earth Metals}, author={} }