Combined lattice-location-hyperfine-interaction experiments on Hg implanted in Fe

Abstract
The channeling technique has been used to study the lattice location of Hg implanted at 80 keV into Fe. The impurity is found to be almost entirely substitutional at a dose of 5 × 1014 ions cm2. Using implanted sources nuclear magnetic resonance of oriented nuclei (NMR/ON) was observed both for FeHg203 and FeHgm197. The FeHg203 resonance observed in an external field of 2.1 kG at 216.4(2) MHz gives Bhf(FeHg)=838.1(8) kG. For FeHgm197 the resonance at 100.9(1) MHz in an applied field of 2.3 kG yields Bhf(FeHg)=839.5(8) kG. Both experiments were performed at temperatures below 1 K. The values of Bhf(FeHg) found in the literature are compared with these values. The difference between the results of time-differential perturbed-angular-correlation experiments at room temperature and the result of the present NMR/ON investigation is ascribed to a temperature anomaly. The hyperfine anomaly Δ(Hgm197Hg203)=+0.17(14)% has been derived. The spin-lattice relaxation times of Hg203 and Hgm197 in iron are T1=61(7) sec and T1=190(40) sec, respectively, at 20 mK.