Abstract
The NMR of in antiferromagnetic Mn has been reexamined, using both superregenerative and pulsed NMR techniques, in the temperature region 1.3-20°K. Instead of the single resonance originally reported, five distinct quadrupolar-split transitions are observed, whose separation yields a value of MHz. The frequency of the central (½ ↔ -½) transition extrapolates to 670.38±0.05 MHz at 0°K. Were there no changes in the hyperfine interaction in going from Zn: Mn to Mn, this would imply in the antiferromagnetic ground state. The magnitude and dependence of the linewidths of the individual transitions are reasonably consistent with the predictions of the Suhl-Nakamura theory (i.e., the indirect nuclear spin-spin interaction via virtual spin-wave excitations). The failure to observe a transient signal is attributed to the very short resulting from the latter interaction.
- Received 9 September 1968
DOI:https://doi.org/10.1103/PhysRev.177.667
©1969 American Physical Society