The change of some magnetic properties of Cr2O3 in the vicinity of TNTN for the paramagnetic state

The observed anomaly of the parallel magnetic susceptibility of Cr2O3is discussed as the effect of the changes of the crystal lattice parameters with temperature and the changes of the exchange parameters in some range above TNTN connected with it. It is shown that the temperature changes of the crystal parameters have an important influence on the behavior of the magnetic specific heat with temperature too. The results of the calculations based on the correlation theory and the modified Oguchi theory are presented.