We develop methods for the accurate description of groundstate correlation energies in extended systems aiming at chemical precision (1 kcal/mol) for a wide class of materials. This will help to establish ab-initio techniques in those areas where high accuracy and validated predictions are important. After establishing accurate reference methods for solids in the first funding phase, we will try to advance simplified diagrammatic methods, such as the random phase approximation (RPA), in several areas.
(i) To make the RPA widely applicable, forces will be implemented.
(ii) To address the remaining inaccuracies of the RPA, all second order diagrams of perturbation theory will be implemented using physically motivated approximations for higher order diagrams.
(iii) The computational efficiency of the diagrammatic methods will be improved, for instance, by expressing all involved quantities using auxiliary local basis functions.
(iv) Finally, we will develop improved starting points for correlated methods, relying on self-consistency within the random phase approximation or improved semi-local functionals.
The transformation to local basis sets (iii) allows the linking of our methods to those for strong correlations developed in P03 (DMFT), P16 (fRG) and P05 (embedding). The improved density functionals (iv) will be explored in close collaboration with P07. The applied projects will benefit from our methods. In particular, we aim to make our methods suitable for magnetic systems (P09, P12, P15) and for systems with weak interactions (P13, P14).
 | Kresse, Georg Principal Investigator, P02 | University of Vienna Computational Materials Physics |
| Marsman, Martijn Participating Researcher, P02 | University of Vienna Computational Materials Physics |
| Klimeš, Jiří Participating Researcher, P02 |
University of Vienna Computational Materials Physics& Charles University in Prague Department of Chemical Physics and Optics
|
 | Hummel, Felix Participating Researcher, P02 | University of Vienna Computational Materials Physics |
 | Maggio, Emanuele Participating Researcher, P02 | University of Vienna Computational Materials Physics |
 | Ramberger, Benjamin Participating Researcher, P02 | University of Vienna Computational Materials Physics |
