Collective potential energy surface calculations have been performed for ${}_{}{}^{74-80}{}_{}{}^{}\mathrm{Kr}$ nuclei in the framework of the Gneuss and Greiner model. The collective Hamiltonian is diagonalized in the basis of the five-dimensional quadrupole oscillator. Our calculations suggest that the ${}_{}{}^{78,80}{}_{}{}^{}\mathrm{Kr}$ nuclei are $\gamma$ unstable with a triaxial minimum at $\gamma \simeq 40°$. The ${}_{}{}^{74,76}{}_{}{}^{}\mathrm{Kr}$ nuclei have two axially symmetric minima with the $0_1^{+}$ ground state being located mainly in the deformed minimum, whereas the first excited $0_2^{+}$ state is located in the spherical minimum. The calculations also indicate that the ground state wave function for ${}_{}{}^{74}{}_{}{}^{}\mathrm{Kr}$ is spread over both the minima.

[NUCLEAR STRUCTURE ${}_{}{}^{74,76,78,80}{}_{}{}^{}\mathrm{Kr}$: Calculated potential energy surfaces; compared with experimental energy levels and $B\left(E2\mathrm{}\right)\mathrm{}$ values.]

• Received 17 May 1983

DOI:https://doi.org/10.1103/PhysRevC.29.284