Hfs ofF19in the Electron Paramagnetic Resonance of Mn: ZnF2

Abstract

An experimental and theoretical re-examination of the ${\mathrm{F}}^{19}$ "super-hfs" in the electron paramagnetic resonance (EPR) of ${\mathrm{Mn}}^{++}$ as a dilute, substitutional impurity in Zn${\mathrm{F}}_2$ has been made. The observation of anomalous spectra at 23 kMc/sec has necessitated a modification of the phenomenological theory first offered by Tinkham. Precise measurement of all of the hfs interaction constants, in conjunction with the new theory, allows direct comparison to be made with the results of the NMR experiments of ${\mathrm{F}}^{19}$ in Mn${\mathrm{F}}_2$. The agreement now found is most satisfactory. The theory of the origin of the ${\mathrm{F}}^{19}$ hfs is discussed in the light of recent work of Mukherji and Das, Marshall, and Keffer et al.