Dresden 2026 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
BP: Fachverband Biologische Physik
BP 14: Poster Session II
BP 14.73: Poster
Dienstag, 10. März 2026, 18:00–21:00, P2
Quantum mechanical/molecular mechanics (QM/MM) calculations for absorption spectra of photoactive proteins, including many-body screening contributions — •Jelena Schmitz1,2, Maximilian Graml1,2, Till Rudack1,3, and Jan Wilhelm1,2 — 1Regensburg Center for Ultrafast Nanoscopy (RUN), University of Regensburg, Germany — 2Institute of Theoretical Physics, University of Regensburg, Germany — 3Structural Bioinformatics, Regensburg Center for Biochemistry, University of Regensburg, Germany
The GW method and the Bethe-Salpeter equation (BSE) capture many-body screening effects, important for the full quantum mechanical description of excitations in large biological structures. Spectral shifts in photoactive proteins resulting from conformational changes can be described using a hybrid quantum mechanics/molecular mechanics (QM/MM) framework [1]. Our work investigates the impact of incorporating GW+BSE in QM/MM calculations, and examines how larger QM regions influence the accuracy of predicted shifts. We aim to compare to experimental results and QM/MM calculations using different ab initio approaches [1]. In order to perform calculations on larger, non-periodic systems, we are implementing RI-DFT as a pre-calculation method within the CP2K software package, prior to GW. This could provide us with access significantly larger system sizes, even full electrostatic protein surroundings, and therefore even higher accuracies.
[1] ChemBioChem 20, 1766 (2019)
Keywords: QM/MM; Bethe-Salpeter equation; Absorption spectra; Many-body perturbation method; Hybrid quantum mechanics/molecular mechanics