Lattice dynamic effects in electron paramagnetic resonance

The electron-phonon interaction for a paramagnetic impurity in an insulating crystal is derived and from that an electron-electron interaction in a higher order is considered. An attempt is made to provide a unified presentation of the effect of phonons on the parameters measured in an electron-paramagnetic resonance experiment. The phonon-induced corrections to the zero-field splitting, the hyperfine field, the superhyperfine splitting and line intensities is reviewed theoretically along with experimental data. Both the point charge and covalent models are discussed. The effect of local and resonance modes is calculated and discussed in terms of isotope effect. Some related problems of the energy levels, dispersion, screening and phonon force are also included in appendices.