The theoretical and numerical developments of the group are mainly situated in the framework of functional theories, in particular static and time-dependent density functional theory (DFT and TDDFT) and Green’s function functional theory, with a particular expertise in Many-Body Perturbation Theory (MBPT). More recently also attempts to design non-perturbative approaches are put forward. The approaches that are developed aim at being general and not limited to a particular class of materials. However, the codes that are developed in the group use a plane wave basis, which privileges extended periodic systems.
Therefore mostly bulk metals or insulators, but also periodic quasi two- and one dimensional structures are studied. The numerous close experimental collaborations are centred on photoemission and inelastic x-ray scattering spectroscopies, especially with synchrotrons, and on electron energy loss spectroscopies, in relation with transmission electron microscopy.