[en] A model with a broken SU(3)-symmetry is applied to the description of the ground and γ-state energies in heavy deformed even-even nuclei. Hamiltonian of the model contains linear combination of operators invariant to the rotation group, but broking the SU(3)-symmetry. The outcoming expression for the energy levels are compared to the predictions of different variants of the unified model. The form and role of the interaction operator in the Hamiltonian is discussed. A comparison between theoretical and experimental results is given