Paramagnetic resonance in dilute iron group fluorides. I. Fluorine hyperfine structure

Abstract A report is given of the paramagnetic resonance spectra of Mn2+, Fe2+, Co2+ and Cr3+ ions present substitutionally in a ZnF2 lattice. The temperature-dependence of the anisotropy of the susceptibility in the case of Fe was also studied. In addition to the usual spin Hamiltonian tensor parameters g, D and A, there are data on the hyperfine structure coupling tensors AN between the magnetic electrons and the surrounding six fluorine nuclei. In all cases except Cr3+, where there are no σ-bonding electrons, the fluorine h.f.s. intervals are of between 10 and 20 G. With Cr3+, no fluorine h.f.s. is resolved. It is suggested that the two types of Cr3+ spectra observed correspond to the two most natural sites for a monovalent charge-compensating cation.