1971 Volume 30 Issue 2 Pages 311-322
Quadrupole effects in NMR on 12B(T1⁄2=20 ms) and 12N(T1⁄2=11 ms) have been investigated by using the polarized nuclei produced and implanted through nuclear reactions and the resultant asymmetric β decay. The implantation media were polycrystalline bcc metals (Nb, Mo, Ta and W), TiB2 and ZrB2. To increase the observable effects in NMR, a frequency-modulated r.f. field was employed. The spectra in bcc metals show the characteristics of quadrupole interaction for nuclear spin I=1h, and the determined coupling constants depend largely on the periodic groups of the related elements. The spectra in the bcc metals together with those in the fcc metals (Al, Cu, Pt and Au) indicate that the major implanted sites are interstitial. From the results on TiB2 and ZrB2 and the known values on 11B, the ratio of quadrupole moments is determined as |Q(12B)⁄Q(11B)|=0.42±0.04, and the moment of 12B is deduced to be |Q(12B)|=0.0171±0.0016 b.
This article cannot obtain the latest cited-by information.