The moments of inertia (MoI) of odd-$A$ and even-even rare-earth nuclei are calculated using the Nilsson + BCS method with and without the blocking effect taken into account. The calculated MoI’s with blocking considered is smaller than that without blocking considered. The MoI of an odd-$A$ nucleus depends strongly on which orbital is occupied by the odd nucleon. Although the calculated MoI’s are systematically smaller than the data, the large fluctuations in the experimental odd-even differences in MoI’s can be reproduced qualitatively. This is contrary to the common assertion that the MoI of an odd-$A$ nucleus is some 15% larger than those of its neighboring even-even nuclei with the BCS theory and is helpful to understand the appearance of normally deformed identical bands in an odd-$A$ nucleus and its even-even neighbors under the mean-field (BCS) approximation.

• Received 1 June 2000

DOI:https://doi.org/10.1103/PhysRevC.63.047305