  Deformation-energy surfaces of 54 even-even isotopes of Pt, Hg and Pb nuclei
with neutron numbers up to 126 are investigated within a
macroscopic-microscopic model based on the Lublin-Strasbourg-Drop macroscopic
energy and shell plus pairing-energy corrections obtained from a Yukawa-folded
mean-field potential at the desired deformation. A new, rapidly converging
Fourier shape parametrization is used to describe nuclear shapes. The stability
of shape isomeric states with respect to non-axial and higher-order
deformations is investigated.
