By introducing a three-body interaction among the d bosons into the Hamiltonian of the interacting boson model, the difficulties concerning the energy spacing between different τ and with the staggering phenomenon in the O(6) dynamical symmetry are surmounted in more or less degree. So the energy spectra of the O(6)-like nuclei are improved, and some E2 transitions which are forbidden in O(6) limit become allowed due to this three-body potential. The energy spectra and B(E2) values of some even-even nuclei are calculated. The theoretical values agree with the experimental data fairly well.

• Received 17 September 1993

DOI:https://doi.org/10.1103/PhysRevC.49.2465