ReaxFF-based nonadiabatic dynamics method for azobenzene derivatives.

Area of Science:

• Computational Chemistry
• Molecular Dynamics
• Photochemistry

Background:

• Azobenzene photoisomerization is crucial in various chemical and biological processes.
• Accurate simulation of excited-state dynamics requires robust computational models.

Purpose of the Study:

• To parameterize ReaxFF reactive force fields for azobenzene and its derivatives.
• To simulate photoisomerization dynamics and predict key properties.
• To assess the transferability and applicability of the developed force fields.

Main Methods:

• Parameterization of ReaxFF reactive force fields for ground and excited states.
• Ab initio calculations for reference data generation.
• Nonadiabatic surface hopping simulations.
• Gas-phase and solution-phase simulations (n-hexane).

Main Results:

• Accurate prediction of azobenzene photoisomerization quantum yields and decay times.
• Demonstrated transferability to arylazopyrazoles and ethylene-bridged azobenzene.
• Successful extension of the model to adsorbates on metal surfaces.
• Simulation of azobenzene-triggered cyclobutene ring-opening.

Conclusions:

• The developed ReaxFF force fields provide a reliable tool for studying azobenzene photoisomerization.
• The model exhibits wide applicability in diverse chemical environments and for related molecules.
• Reactive force fields offer significant advantages for simulating complex photochemical reactions.