An isomer, with ${\mathit{t}}_{1/2}$=35±10 ns and J,${\mathit{K}}^{\mathrm{\pi }}$=14,${14}^{+}$, has been observed in the nucleus ${}_{}{}^{176}{}_{}{}^{}\mathrm{W}$ using the reaction ${}_{}{}^{150}{}_{}{}^{}\mathrm{Nd}$${(}^{30}$Si,4n) at a beam energy of 133 MeV. The isomer exhibits an unusual pattern of decay in which the majority of the flux proceeds directly to states with 〈K〉=0, bypassing available levels of intermediate K. This severe breakdown of normal K-selection rules in ${}_{}{}^{176}{}_{}{}^{}\mathrm{W}$ is compared with recent observations of K violation in neighboring nuclei, within the framework of proposed theoretical approaches. The available data on these K-violating decays seem to have a consistent explanation in models of K mixing which include large-amplitude fluctuations of the nuclear shape. © 1996 The American Physical Society.

• Received 6 February 1995

DOI:https://doi.org/10.1103/PhysRevC.53.1173