We can also add, in case of proton, a Coulomb potential. The Woods-Saxon potential has been widely used in parametrizations of effective single-particle potentials.

However, as was the case with the harmonic oscillator, none of these potentials are linked directly to the nuclear forces.

Our next step is to build a mean field based on the nucleon-nucleon interaction. This will lead us to our first and simplest many-body theory, Hartree-Fock theory.