EPR parameters and superposition model analysis for trigonal Dy3+-O2- center in CaF2 crystal

摘要

On the basis of the defect model of trigonal Dy3+-O2- center in CaF2, the EPR parameters (g factors and hyperfine structure constants) for this trigonal center are calculated from the perturbation formulas. In the formulas, the contributions to EPR parameters due to the J-mixing among H-6(J) (J = 15/2, 13/2 and 11/2) states, the mixtures among the states with the same J-value and those between the lowest Kramers doublet Gamma(gamma) and other Kramers doublets Gamma(X) are included. In the calculation, the crystal field parameters are estimated from the superposition model. From the calculation, the EPR g factors g(), g(perpendicular to) are reasonably explained and the superposition model intrinsic parameters (A) over bar (2)(F-) and (A) over bar (2) (O2-) with R = 2.366 Angstrom are obtained. (C) 2003 Elsevier B.V. All rights reserved. [References: 19]