On Ratios of B(E2)'s

We have conducted a wide survey of the ratio B(E2; 4+to2+ ) / B(E2; 2+ to zero+ ) throughout the periodic table. In the rotational model this ratio is 10/7 and in the vibrational model it is 2/1(stimulated emission) There are considerable deviations from this for magic or semi-magic nuclei e.g. for 86Kr (N=50) the ratio is close to zero. But what is more surprising is that there are large deviations for other nuclei as well, which will be systematically shown. Theoretical discussions for some of these deviations will be given.