SKM 2021 – wissenschaftliches Programm
CPP 13.5: Vortrag
Freitag, 1. Oktober 2021, 11:30–11:45, H3
Optimally-tuned range-separated hybrid functionals for accurate molecular excited-state geometries — •Bernhard Kretz and David A. Egger — Technical University of Munich, Germany
Molecular excited-state (ES) potential energy surfaces (PES) obtained by computational methods can shed light on reaction mechanisms and pathways in photocatalytic reactions. These ES PES can be calculated using either time-dependent density functional theory (TD-DFT) or high-level wave-function methods. TD-DFT based calculations are computationally very efficient, but often lack the accuracy achieved by computationally more expensive wave-function methods. Recently, the class of optimally-tuned range-separated hybrid (OT-RSH) functionals was developed which promises to reduce the gap in accuracy.
In our recent work, by comparison with high accuracy wave-function data from literature, we assessed the accuracy of TD-DFT and OT-RSH for the excited-state geometries for a selection of organic molecules with varying complexity of their ES PES. We mainly focused on the structural parameters of the lowest-excited singlet states. Our results show that OT-RSH maintains the accuracy of conventional functionals for small molecules, while it improves the description of more complex ES PESs involving charge-transfer states.
 C. Azarias, J. Phys. Chem. A, 121, 32, 6122 (2017)
 L. Kronik et al., J. Chem. Theory Comput., 8, 5, 1515 (2012)
 B. Kretz and D. A. Egger, J. Chem. Theory Comput., 17, 1, 357 (2021)