An approximate method, recently proposed to include in continuum solvation models the
effects of electronic charge lying outside the solute cavity, has been adapted and
implemented in the framework of the polarizable continuum model PCM. This formulation
exploits all the features already developed for the other PCM versions; it provides molecular
free energies, gradients and second derivatives with respect to nuclear coordinates. The
performances of this method have been tested in comparison with other PCM versions, in …