THE CRYSTAL-FIELD AND EXCHANGE INTERACTIONS IN NDNI5, UGA2 AND UPD2AL3

Magnetic and electronic properties of the hexagonal NdNi5, UGa2 and UPd2Al3 have been reviewed within a crystalline electric field approach in combination with exchange interactions. The fine electronic structure in these compounds associated with the Nd3+ and U3+ ions have been derived. The Nd3+ and U3+ ions, as Kramers f(3) systems, have the Kramers doublet ground state. In all compounds the Kramers doublet Gamma(8) is the charge-formed ground state. The calculations reproduce all known experimental observations, in particular the observed ordered magnetic moment and Curie or Neel temperature.