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Nonadiabatic dynamics starting from reactant and transition state in luminol chemiluminescence
Jian-Ge Zhou1, Yinan Shu2, Gabrielle Williams1
1Department of Chemistry, Physics and Atmospheric Sciences, Interdisciplinary Nanotoxicity Center, Jackson State University, Jackson, Mississippi 39217, USA.
The Journal of Chemical Physics
|June 22, 2026
Summary
Starting configurations significantly impact nonadiabatic dynamics. Luminol chemiluminescence dissociation times differ, but chemiexcitation yields remain similar, revealing insights into reaction pathways.
Area of Science:
- Chemical Physics
- Quantum Chemistry
- Reaction Dynamics
Background:
- Nonadiabatic dynamics are crucial for understanding chemical reactions.
- Surface hopping is a key method for simulating these dynamics.
- Luminol chemiluminescence provides a model system for studying chemiexcitation.
Purpose of the Study:
- To investigate the influence of initial configurations on nonadiabatic dynamics.
- To analyze dissociation times and chemiexcitation yields in luminol chemiluminescence.
- To elucidate the mechanisms behind singlet and triplet chemiexcitation.
Main Methods:
- Trajectory surface hopping simulations were employed.
- Comparisons were made between trajectories starting from reactant and transition states.
- Analysis focused on dissociation times and state-to-state excitation/de-excitation processes.
Main Results:
- Dissociation times were significantly longer for trajectories starting from the reactant compared to the transition state.
- Chemiexcitation yields were nearly identical for both starting configurations.
- A significant singlet chemiexcitation yield was observed, attributed to an imbalance in S0-S1 excitations and S1-S0 de-excitations.
- The negligible triplet yield was explained by similar de-excitation processes.
Conclusions:
- Initial configurations play a critical role in the temporal evolution of nonadiabatic dynamics.
- Chemiexcitation yields are robust to the choice of starting configuration in this system.
- The chemiexcitation region, distinct from the intrinsic reaction path, is responsible for the observed singlet yield.
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