Magnetic properties and crystal electric field of Pr2CuO4 and Nd2CuO4

The contribution of the crystalline electric field (CEF) effects to the magnetic susceptibility of lanthanide cuprates Pr2CuO4 and ND2CuO4 have been investigated theoretically. The other sources of magnetic moments (paramagnetic Cu-ions, electrons of conductivity, excited multiplets of RE-ions) result in a contribution to the susceptibility which amounts only to about 1% of that of the CEF effects. Deviations from the Curie-Weiss law at low temperatures and the linear dependence of the reversed susceptibility χ-1 on the temperature in the range 100-300 K (which have been found in experiments with polycrystalline samples of the compounds mentioned) can be explained by the peculiarities of the CEF level schemes of Pr3+ and Nd3+ ions. The anisotropy of the magnetic properties of Pr2CuO4 and Nd2CuO4 monocrystals is predicted as well as the antiferromagnetic character of the exchange interaction of RE-ions