A model based on a static quadrupole and octupole deformation of the intrinsic nuclear shape gives an accurate description of the low-energy level spectrum and wave functions in ${}_{}{}^{227}{}_{}{}^{}\mathrm{Ac}$. Major discrepancies between strong-coupling theory and experiment are removed by taking into account the nonadiabaticity of the nucleonic motion.

• Received 23 June 1986

DOI:https://doi.org/10.1103/PhysRevC.35.1145