Full density-functional theory

Add the remaining terms in Eqs. (7,9), those involving $\epsilon_{xc}$ and $\epsilon_{xc}'$, to get() and H(). You may use the functions excVWN() and excpVWN() in Appendices A and B, which implement the operators $\epsilon_{xc}(\vec n)$ and $\epsilon_{xc}'(\vec n)$, respectively, from the same functions used in our $d=1$ dimensional solver for atoms.