Developments in electronic structure theory
Physical properties of atoms, molecules and solids are determined by the collective behavior of electrons interacting with each other and with the nuclei. Unfortunately, an analytical solution of the electronic problem in a realistic system is often out of reach and one must resort to a numerical approach. In our group we contribute to developing various computational methods to solve the electronic problem in atoms, molecules and solids.
The most substantial part of our activity is focused on methods to solve the fundamental equation of density functional theory, the Kohn-Sham equation. They comprehend full-potential methods like Elk and RSPt, which are based on linear augmented plane waves and linear muffin-tin orbitals, respectively. In RSPt, we also develop computational techniques for treating strongly correlated materials, based on the dynamical mean-field theory (DMFT). A database of electronic structure has also been developed. Other methodological developments are also being pursued, e.g. a real-space electronic structure method that calculates the Green's function of the valence band states using recursion expressions and the continued fraction method, as well as the exact muffin-tin orbitals method (EMTO). The division also hosts developments of tight-binding methods that are used for calculations of e.g. topological states or the damping parameter of the Landau-Lifshitz-Gilbert equation.