Paramagnetic Resonance II

In this report, which is complementary to that of Bleaney and Stevens in Reports on Progress in Physics, Volume XVI, paramagnetic resonance data are collected together for crystalline solids containing ions of the transition groups, and those parts of the theory necessary for an understanding of the results are presented in a fairly simple way. After a brief introduction, the magnetic properties of various types of compounds are considered, and a simple discussion is given of the spin Hamiltonian which is used to describe the lowest energy levels. Some details are also given of the structures of the ten crystal types which are most commonly used, and of the relation between the structure and the resonance spectrum of a single crystal. Finally, the resonance data which are available for ions of the 3d, 4d, 5d, 4f and 5f transition groups are tabulated. These data are expressed as values of the parameters in the appropriate spin Hamiltonian, and, where applicable, formulae are given for (1) energy levels, (2) susceptibility, (3) specific heat tail CT²/R, in terms of these parameters.