For the gravitational equivalent the charge density will be replaced by the mass density. The sun can be seen as a nucleus with the other planets orbiting it as the electrons, we then have:
T_0 = The kinetic energy of a planet;
V_H = The potential a planet ‘feels’ in the gravitational field determined by the other planets;
V_ext = The potential a planet ‘feels’ in the gravitational field determined by the sun;
V_xc = The potential determined by the exchange correlation of individual planets.