Homework Statement
Real atomic nuclei are not point charges, but can be approximated as a spherical distribution with radius ##R##, giving the potential
$$ \phi(r) = \begin{cases}
\frac{Ze}{R}(\frac{3}{2}-\frac{1}{2}\frac{r^2}{R^2}) &\quad r<R\\
\frac{Ze}{r} &\quad r>R \\...