Investigations of the g factors for Co2+ in fluoroperovskites

The perturbation formula of g factor for 3d(7) ion in cubic octahedral crys tals has been obtained from a cluster approach. In the formula, the paramet ers related to the configuration interaction and the covalency reduction ef fect can be obtained from the optical spectra of the crystal under study an d so no adjustable parameters are applied. From the formula, the g factors for Co2+ in fluoroperovskites LiBaF3, KMBF3, KZnF3 and CsCdF3 are calculate d. The calculated results are in agreement with the observed values. The g factor following the order of LiBaF3 : Co2+ < KMgF3 : Co2+ < KZnF3: Co2+ < CsCdF3 : Co2+ is also explained. (C) 2000 Elsevier Science B.V. All rights reserved.