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Nonadiabatic rare events from transition-path sampling of MASH trajectories
Danial Ghamari1, Jeremy O Richardson1
1Institute of Molecular Physical Science, ETH Zurich, 8093 Zurich, Switzerland.
The Journal of Chemical Physics
|May 4, 2026
Summary
This study introduces a new computational framework combining mapping approach to surface hopping (MASH) and transition-path sampling to efficiently simulate rare nonadiabatic reactions, enabling detailed analysis of molecular processes.
Area of Science:
- Computational Chemistry
- Chemical Dynamics
- Quantum Mechanics
Background:
- Rare nonadiabatic reactions are crucial in molecular processes.
- Direct dynamical simulations struggle to capture these events efficiently.
Purpose of the Study:
- To develop an efficient computational framework for simulating rare nonadiabatic reactions.
- To enable detailed analysis of reaction mechanisms and properties.
Main Methods:
- Combined mapping approach to surface hopping (MASH) with transition-path sampling.
- Ensured MASH trajectories are Markovian, time-reversible, and obey Liouville's theorem.
- Applied the method to a spin-boson model.
Main Results:
- Generated unbiased nonadiabatic reactive pathways.
- Enabled analysis of statistical and dynamical properties, including rate constants.
- Demonstrated a practical and systematic tool for rare nonadiabatic processes.
Conclusions:
- The developed framework efficiently simulates rare nonadiabatic events.
- Provides insights into reaction mechanisms and dynamics.
- Offers a valuable tool for complex molecular processes beyond brute-force simulations.
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