Brazilian Journal of Physics
Print version ISSN 0103-9733
ZHANG, Zhi- Hong; WU, Shao- Yi; XU, Pei and LI-LI, Li. Theoretical studies of the EPR parameters for Ni2+ and Co+ in MgO. Braz. J. Phys. [online]. 2010, vol.40, n.3, pp.361-364. ISSN 0103-9733. http://dx.doi.org/10.1590/S0103-97332010000300020.
The electron paramagnetic resonance (EPR) parameters (g factors and the hyperfine structure constants) for Ni2+ and Co+ in MgO are theoretically studied from the perturbation formulas of these parameters for a 3d8 ion in octahedral crystal-fields. In the computations, the ligand orbital and spin-orbit coupling contributions are taken into account using the cluster approach. The calculated EPR parameters are in good agreement with the experimental data. The larger g factor and the smaller magnitude of the hyperfine structure constant for Ni2+ as compared with those for Co+ can be attributed to the higher spin-orbit coupling coefficient and the lower dipolar hyperfine structure parameter of the former, respectively.
Keywords : Impurity and defects; Electron paramagnetic resonance; Ni2+; Co+; MgO.