  The Deformation Dependent Mass (DDM) Kratzer model is constructed by
considering the Kratzer potential in a Bohr Hamiltonian, in which the mass is
allowed to depend on the nuclear deformation, and solving it by using
techniques of supersymmetric quantum mechanics (SUSYQM), involving a deformed
shape invariance condition. Analytical expressions for spectra and wave
functions are derived for separable potentials in the cases of gamma-unstable
nuclei, axially symmetric prolate deformed nuclei, and triaxial nuclei,
implementing the usual approximations in each case. Spectra and B(E2)
transition rates are compared to experimental data. The dependence of the mass
on the deformation, dictated by SUSYQM for the potential used, moderates the
increase of the moment of inertia with deformation, removing a main drawback of
the model.
