Deviation of the SUq(2) prediction from observations in even-even deformed nuclei

The validity of the quantum group SUq(2) expression for the nuclear rotational spectrum is investigated thoroughly. Analysis [including the Mallmann plots, the relations for the I(I+1) expansion coefficients, energy spectra, etc.] definitely display a systematical deviation of the Suq(2) prediction from the experimental data available for the even-even rare-earth and actinide nuclei. Only within a limited range of angular momentum the Suq(2) expression is suitable for rotational spectra. A significant angular momentum dependence of the q-deformation parameter is found. The q deformation is directly related to the nuclear softness. © 1991 The American Physical Society.