Theoretical investigations of EPR parameters for trigonal Sm ion in La2Mg3(NO3)1224H2O crystal

The electron paramagnetic resonance parameters g factors g and g of Sm3+and hyperfine structure parameters A and A of 147Sm3+ and 149Sm3+ isotopes in La2Mg3(NO3)12*24H2O crystal are calculated from the perturbation formulas of EPR parameters for 4f5 ion in trigonal symmetry. In these formulas, the J-mixing among the 6HJ (J=5/2, 7/2 and 9/2) states via crystal-field interactions, the mixtures among the states with the same J value via spin-orbit coupling interaction, and the interactions between the lowest Kramers doublet Gammagamma and the same irreducible representations in the other 11 Kramers doublets Gammax via crystal-field and orbital angular momentum (or hyperfine structure) interactions are considered. The crystal-field parameters for the studied Sm3+ centre are obtained from the superposition model. The theoretical calculated results are in reasonable agreement with the experimental values.