Theoretical investigations of EPR parameters for trigonal Sm3+ ion in La2Mg3(NO3)12·24H2O crystal

Abstract

Abstract The electron paramagnetic resonance parameters g factors g ∥ and g ⊥ of Sm 3+ and hyperfine structure parameters A ∥ and A ⊥ of 147 Sm 3+ and 149 Sm 3+ isotopes in La 2 Mg 3 (NO 3 ) 12 ·24H 2 O crystal are calculated from the perturbation formulas of EPR parameters for 4f 5 ion in trigonal symmetry. In these formulas, the J -mixing among the 6 H J ( 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 Γγ and the same irreducible representations in the other 11 Kramers doublets Γx via crystal-field and orbital angular momentum (or hyperfine structure) interactions are considered. The crystal-field parameters for the studied Sm 3+ centre are obtained from the superposition model. The theoretical calculated results are in reasonable agreement with the experimental values.