[en] The influence of the members of the collective vibrational band on the properties of the collective and non-collective low-lying states is investigated in the framework of the quasiparticle-phonon model. For this purpose the model basis is extended to include up to five-phonon model components by means of a recurrent procedure for solving the equations for the energies and the structure of the excited states. The numerical estimations presented in the paper show that this influence appears to be considerable. 2 tabs., 9 refs. (author)