Hilke Bahmann (University Wuppertal)

Abstract

Hilke Bahmann

University Wuppertal

For complex systems with interfaces, such as models of dye-sensitized solar cells, the performance of hybrid functionals is often limited due to system-dependent parameters that control the overall amount of exact exchange. This can be overcome by introducing a real-space dependent exact-exchange admixture, as in local hybrids, or a density-dependent range-separation function, as in exchange functionals with local range-separation (LRS).

The influence and drawbacks of using exact-exchange at long-range is investigated for the description of level alignments at dye-semiconductor interfaces. As a possible improvement recent LRS functionals are discussed. It is shown that they are especially suited for band gaps of molecules and small TiO2 cluster and thus promising candidates for the electronic states in composite systems.