Transferred hyperfine interaction at 295 K between the rare-earth ions and the fluorine and lithium nuclei in lithium rare-earth fluorides

The nuclear-magnetic-resonance rotation spectra for the fluorine and lithium nuclei in LiTb${\mathrm{F}}_4$, LiDy${\mathrm{F}}_4$, LiHo${\mathrm{F}}_4$, and LiEr${\mathrm{F}}_4$ have been obtained at 295 K. They are separated in contributions from the dipole and the transferred hyperfine interactions. In general, the latter consists of an isotropic part and an anisotropic part. The anisotropic part turns out to be very small in all cases when the uniaxial anisotropy of the susceptibility of the crystal has been accounted for. Both for fluorine and lithium the isotropic transferred hyperfine interaction is found to make the local field lower than the applied field. The results are discussed in view of current theories.