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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
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QM/MM Nonadiabatic Dynamics: the SHARC/COBRAMM Approach
Davide Avagliano1, Matteo Bonfanti2, Marco Garavelli2
1Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, A-1180 Vienna, Austria.
Journal of Chemical Theory and Computation
|June 11, 2021
Summary
We developed the SHARC/COBRAMM approach for efficient excited-state dynamics simulations. This method models nonadiabatic processes in complex environments, aiding in understanding light-induced molecular behavior.
Area of Science:
- Computational Chemistry
- Theoretical Chemistry
- Physical Chemistry
Background:
- Simulating excited-state dynamics in complex environments is crucial for understanding photochemical processes.
- Accurate modeling requires methods that handle nonadiabatic effects and environmental interactions.
Purpose of the Study:
- To present the SHARC/COBRAMM approach for efficient excited-state dynamics simulations.
- To provide a modular framework for modeling nonadiabatic processes using quantum mechanics/molecular mechanics (QM/MM).
Main Methods:
- Utilized the SHARC (Surface-hopping including ARbitrary Couplings) method for trajectory surface-hopping.
- Employed COBRAMM for ground- and excited-state QM/MM calculations with electrostatic embedding and a hydrogen link-atom approach.
- Combined free and open-source packages for a comprehensive simulation framework.
Main Results:
- Demonstrated the SHARC/COBRAMM approach for easy and efficient excited-state dynamics simulations.
- Successfully modeled nonadiabatic and spin-orbit couplings in molecular systems.
- Provided an example of acrolein relaxation from S1 to T1 in solution.
Conclusions:
- The SHARC/COBRAMM approach offers a powerful tool for atomistic to nanoscale modeling of nonadiabatic processes.
- This method facilitates the study of molecular behavior after light irradiation in various environments.
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