Modeling Multistate Photodynamics of Azobenzene Using Hybrid Computational Scheme

Area of Science:

• Computational chemistry
• Photochemistry
• Molecular dynamics

Background:

• Nonadiabatic dynamics govern molecular behavior after light absorption.
• Accurate modeling of excited states is crucial for understanding photochemical reactions.
• Azobenzene photoisomerization is a key model system for studying these processes.

Purpose of the Study:

• To develop and validate a hybrid computational scheme for multistate nonadiabatic molecular dynamics.
• To model the gas-phase photodynamics of trans- and cis-azobenzene.
• To accurately reproduce experimental quantum yields of photoisomerization.

Main Methods:

• A hybrid computational scheme combining linear-response and state-averaged methods.
• Time-dependent density functional theory (TDDFT) for excited states.
• Ensemble density functional theory for population transfer.
• Modeling gas-phase photodynamics of azobenzene isomers.

Main Results:

• The hybrid scheme accurately reproduces the ~2-fold difference in quantum yield for trans-azobenzene photoisomerization.
• The method successfully models population transfer among electronically excited states.
• Simulations align with experimental data and other theoretical studies.

Conclusions:

• The proposed hybrid computational scheme offers a reliable method for simulating multistate photochemical processes.
• This approach enhances the understanding of molecular photodynamics.
• The validated protocol can be applied to various molecular systems.