Quantum 2025 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

THU: Thursday Contributed Sessions

THU 4: Precise Quantum Molecules: Contributed Session to Symposium

THU 4.4: Vortrag

Donnerstag, 11. September 2025, 15:00–15:15, ZHG004

Quantum-mechanical calculations for million-atom biological systems — •Luc Wieners and Martin E. Garcia — Institut für Physik, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany

Quantum-mechanical first-principles calculations are commonly only used for systems containing a few hundred atoms which leaves biological systems with thousands or millions of atoms inaccessible. In this study we show a new algorithm for the Hartree-Fock method combined with a divide-and-conquer approach which enables calculations of million-atom biological systems, including a whole bacteriophage in a solution which in total contains 45 million atoms.

The high computational speed also allows the calculation of spectra for systems with hundreds to a few thousand atoms. This is used to compute absorption spectra for proteins, DNA and medications. Additionally, Hartree-Fock atomic energies are found to coincide with AlphaFold's pLDDT confidence score for protein structure predictions, showing a connection between first-principle calculations and protein structure assessment.

We anticipate that the presented methods open a pathway to fully quantum-mechanical investigations including more accurate molecular dynamics simulations and theoretical predictions of spectral properties for systems in biology and medicine.

Keywords: Hartree-Fock; biophysics; absorption spectra; AlphaFold; large-scale quantum physics