Theoretical Investigations of the Electron Paramagnetic Resonance g Factors for the Trivalent Cerium Ion in LiYF₄ Crystal

Abstract

The perturbation equations of the EPR parameters g and g ⊥ for the lowest Kramers doublet of a 4f 1 ion in tetragonal symmetry are established. In these equations, the contributions of the covalency effects, the admixture between J = 7/2 and J = 5/2 states and the second-order perturbation (which is not considered previously) are included. The crystal field parameters for the studied Ce 3+ center are calculated from the superposition model. Based on the above perturbation equations and related parameters, the EPR g factors for the Ce 3+ center in LiYF 4 crystals are reasonably explained. The results are discussed.