Superhyperfine Structure in the EPR Spectrum of CdF2:Eu

The superhyperfine structure (shfs) of Eu²⁺ in the EPR spectrum of CdF₂:Eu has been examined experimentally. The results have been analyzed using the formalism of Ranon and Hyde with the aid of Valentin's recent determination of the overlap contribution to the shfs. This analysis has yielded correctly the number of EPR lines observed, the magnitude of the splitting between them, and their relative intensity. It is shown that the shfs arises primarily from the fluorine nuclear Zeeman interaction, but that the intensities and splittings of the lines are influenced by the overlap between the Eu²⁺ $\text{4f}$ electrons and the nuclear magnetic moments of the surrounding fluorine ions.