Interaction of magnetic ions with phonons

The magnetoelastic interaction leads to shifts in equilibrium positions of the ions for the static part of the interaction and to magnetic ion-phonon effects for the dynamic part. The various effects which result from this interaction are discussed. The author shows how this interaction leads to changes in the phonon and magnon spectra in the case of magnetically ordered materials, how it can give rise to structural transitions in the case of strong magnetoelastic coupling, how it can lead to critical effects for sound propagation near phase transitions and to various other effects. (Auth.)