g-factors of rotational states in 176Hf and 180Hf were measured with the twelve detector IPAC-apparatus of our laboratory. The natural radioactivity 3.78·1010a 176Lu and the 5.5 h isomer 180mHf were used which populate the ground-state rotational bands of 176Hf and 180Hf.
The integral rotations of gamma - gamma directional correlations in strong external magnetic fields and in static hyperfine fields of (Lu to Hf)Fe2 and HfFe2 were observed. The following results were obtained:
176Hf: g(41+)=+0.334(38)
180Hf: g(21+)=+0.305(14); g(41+)=+0.358(43); g(61+)/g(41+)=+0.95(12).
The hyperfine field in (Lu to Hf)Fe2 was calibrated by observing the integral rotation of the 9/2- first excited state of 177Hf populated in the decay of 6.7d 177Lu. The g-factor of this state was redetermined in an external magnetic field as 177Hf: g(9/2-)=+0.228(7). Finally the g-factor of the 21+ state of 176Hf was derived from the measured g(21+) of 180Hf by use of the precisely known ratio g(21+,176Hf)/g(21+,180Hf) as 176Hf: g(21+)=+0.315(30).