  The model-QED-operator approach [Phys. Rev. A 88, 012513 (2013)] to
calculations of the radiative corrections to binding and transition energies in
atomic systems is extended to the range of nuclear charges $110 \leqslant Z
\leqslant 170$. The self-energy part of the model operator is represented by a
nonlocal potential based on diagonal and off-diagonal matrix elements of the ab
initio self-energy operator with the Dirac-Coulomb wave functions. The
vacuum-polarization part consists of the Uehling contribution which is readily
computed for an arbitrary nuclear-charge distribution and the Wichmann-Kroll
contribution represented in terms of matrix elements similarly to the
self-energy part. Performance of the method is studied by comparing the
model-QED-operator predictions with the results of ab initio calculations. The
model-QED operator can be conveniently incorporated in any numerical approach
based on the Dirac-Coulomb-Breit Hamiltonian to account for the QED effects in
a wide variety of superheavy elements.
