Zero‐field splitting and g‐Values of d8 ions in a trigonal crystal field

Abstract
On the basis of the crystal‐field theory the zero‐field splitting and g‐values of the 3A2 ground state for d8 impurity ions in a trigonally distorted octahedral field are calculated. Using perturbation theory the analytical expressions connecting the spin‐Hamiltonian parameters with the crystal‐field parameters are obtained. It is shown that experimental data for Cu3+ in Al2O3, and Ni2+ in Al2O3, α‐LiIO3, LiNbO3 can be explained taking into account the influence of all the excited levels on the ground state.