Schottky anomaly

The Schottky anomaly, in specific heat measurements, is found in materials with spin energy levels.

At low temperatures, crystalline materials have a heat capacity dependence approximately proportional to the cube of the temperature. This heat capacity corresponds to the population of phonons (collective vibrations of the network).

A magnetic compound (which presents magnetic interactions) will have, superimposed on this function, a low intensity peak, corresponding to the temperature at which the magnetic energy levels are populated.