We have reinvestigated the beta decay of 120 Ag to levels in 120 Cd. Significant deviations in the decays of low-lying states from that expected from a U(5) nucleus have been observed. The results from this paper which include the 0 + 2 and 3 + 1 states (which have now been correctly identified), and previous work on lighter Cd isotopes strongly suggest that the anharmonic vibrator description of the even-even Cd isotopes is inadequate. Analysis of the decay patterns and half-life information

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... d to the determination that there are three beta-decaying isomers in 120 Ag, with J π assignments of (0 − , 1 − ), 4( + ), and 7( − ). In addition, we have identified four candidates of the quadrupoleoctupole quintuplet. These states are J π = (5 − ) at 2489.5 keV, (4 − ) at 2208.4 keV, (2 − ) or (3 − ) at 2318.4 keV, and (1 − ) or (2 − ) at 2448.7 keV. All show strong transitions to the previously known 3 − octupole state at 1898.9 keV. The overall level scheme of 120 Cd has been significantly expanded.