Variational Approach to the Calculation of the Dielectric Function of an Electron Gas: Exchange and Collisions

In a recent work of Woo and Jha, the exchange correlations in a uniform electron gas were calculated. They ignored the Coulomb correlations completely. To describe the physical properties of an electron gas at metallic densities, we propose a variational method to calculate the dielectric function which takes into account the local-field corrections due to both Coulomb and exchange holes.