The self-screening correction to RPA and GW – A model and ab initio study
The self-screening error in the GW approximation is studied by applying correction schemes beyond the random-phase approximation in model and ab inito calculations. Two model systems in the form of Hubbard dimers, with one and two orbitals per site respectively, are considered. Both the self-screening (GW-ss) and self-polarization (GW-sp) correction schemes are compared to ordinary GW calculations
