The axially symmetric rotor plus quasiparticle model for an odd nucleus is generalized to the odd-odd nucleus and special attention is paid to the model basis accounting for γ vibration perturbation around axial symmetry. The method presented in this paper is used for a number of realistic nuclei in the $A=160\mathrm{}$ mass region. Two slightly different calculation schemes are put into practice. The first calculation gives results in qualitative agreement with experiments and the second calculation provides remarkable improvements to the first. A possible explanation of the mechanism for signature inversion of odd-odd nuclei is discussed.

• Received 13 December 1996

DOI:https://doi.org/10.1103/PhysRevC.56.175