Investigation of the EPR parameters of a trigonal Dy3+ center in La2Mg3(NO3)12.24H2O crystal

The electron paramagnetic resonance parameters g(parallel to) and g(perpendicular to) of Dy3+, and the hyperfine structure parameters A(parallel to) and A(perpendicular to) of Dy-161(3+) and Dy-163(3+) in a La2Mg3(NO3)(12) center dot 24H(2)O crystal are calculated by the perturbation formulas of the EPR parameters for a 4f(9) ion in trigonal symmetry. In these formulas, the J-mixing among the (6)Hj (J = 15/2, 13/2 and 11/2) states via crystal-field interactions, the mixtures of the states with the same J-value via spin-orbit coupling interaction and the interactions between the lowest Kramers doublet Gamma(gamma) and the same irreducible representations in the other 20 Kramers doublets Gamma(chi) via the crystal-field and orbital angular momentum (or hyperfine structure) are all considered. The crystal-field parameters for the studied Dy3+ center are obtained with the superposition model. The calculated results are in good agreement with the observed values.