Polarized ll6In nuclei have been produced by capture of polarized thermal neutrons in several In compounds. At temperatures T below 77 ~ and magnetic field strengths H o of several kOe, asymmetries of a few percent of the t-decay of the II6In ground state could be observed in polycrystalline In_P, InAs and InSb, thus indicating the nuclear polarization. Nuclear magnetic resonance signals have been measured with the result for the magnetic moment ai(l16In)=2,7723 (10)nm (uncorrected). t-decay asymmetry and spin lattice relaxation time T 1 have been studied as a function of H 0 and T. The effect of H 0 is to decouple the hyperfine interaction caused by the capture-7 recoil process. However, H 0 has no influence upon T 1, which demonstrates the absence of nuclear relaxation due to paramaguetic impurities. T 1 is determined by quadrupolar relaxation. A quadrupole moment Q (116In)= 0.09 (2) b was calculated by comparison of the a16In relaxation rates with those of the stable 11Sin isotope in the same compounds. Above 30 ~ the temperature dependence of lIT 1 agrees with a recent theoretical investigation. Below 30 ~ the relaxation rate shows an anomalous behaviour, which can be explained by resonance modes due to recoil lattice defects.

The gj-values of the lowest 3Pl-states of Sr and Ba have been determined with optical double resonance. The measurement has been carried out by observation of radiofrequency transitions Amj= 4-1 between Zeeman levels of the even isotopes. Calibration of the magnetic field has been done by optical pumping of the 32S~/2 ground state of the sodium atom. The results are: g~Xp (5 s 5 p aP1, Sr) = 1.50065 (4) g~Xp (6 s 6p aP 1, Ba) = 1.49651 (7).

Nuclear magnetic resonance of ll~ has been observed in silver halides using the polarized neutron capture, fl decay anisotropy method. The magnetic moment was determined as ~I (la~ 2.7084 (5) nm (uncorrected).

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