Nuclear shape isomers

We calculate potential-energy surfaces as functions of spheroidal ( ϵ 2 ), hexadecapole ( ϵ 4 ), and axial-asymmetry ( γ ) shape coordinates for 7206 nuclei from A = 31 to A = 290 . We tabulate the deformations and energies of all minima deeper than 0.2 MeV and of the saddles between all pairs of minima. The tabulation is terminated at N = 160 . Our study is based on the FRLDM macroscopic–microscopic model defined in Atomic Data and Nuclear Data Tables [P. Möller, J.R. Nix, W.D. Myers, W.J. Swiatecki, At. Data Nucl. Data Tables 59 (1995) 185]. We also present potential-energy contour plots versus ϵ 2 and γ for 1224 even–even nuclei in the region studied. We can identify nuclei for which a necessary condition for shape isomers occurs, namely multiple minima in the calculated potential-energy surface. We find that the vast majority of nuclear shape isomers occur in the A = 80 region, the A = 100 region, and in a more extended region centered around 208Pb. A calculated region of shape isomers that has so far not been extensively explored is the region of neutron-deficient actinides “north-east” of 208Pb.