Mössbauer study of the electromagnetic properties of the 69.6-keV level in Os 189
The 69.6-keV level with spin 5/2− in189Os was investigated by the recoilless resonance absorption technique. Its magnetic moment was found to beμ (5/2)=(0.977±0.014)μN. From the measured ratio of the excited and ground-state electric quadrupole moments,Q(5/2)/Q(3/2)=−0.79±0.09, the excited-state quadrupole momentQ(5/2)=−(0.72±0.11)b could be derived. TheE2/M1 mixing parameter of the 69.6-keV ground-state transition was found to beδ=+0.69±0.10. The results are interpreted in terms of two low-energy rotational bands with strong Coriolis mixing.