Description of the shape of medium and heavy nuclei using a finite deformed one-particle potential with deformation-dependent diffuseness

Adjustment of the behavior of the potential energy of nuclear deformation, defined as the sum of the energies of lowest-lying occupied single-particle levels in a deformed finite potential with a pairing correction, is considered by taking into account the dependence of the diffuseness of the surface of the potential on deformation. To verify this approach we construct a non-axial ellipsoidally-deformed potential with a slight (of the order of 1\%) variation of the surface diffuseness at moderate deformations. Parameters of the variation are determined from a calculation for a group of 36 deformed, transitional, and spherical nuclei in the range $50 \le A \le 241$ using existing experimental data on static quadrupole moments. In order to test the performed parameter choice, we applied the model to description of the ground-state deformation of the isotopic chains $^{95-132}$Cd and $^{74-106}$Sr. The obtained description of the ground state deformation of the considered nuclei is in agreement with experimental data and results of macro-microscopic models and calculations using the Hartree-Fock-Bogoliubov method.