AIMD-Based Protocols for Modeling Exciplex Fluorescence Spectra and Inter-System Crossing in Photocatalytic...

Area of Science:

• Computational chemistry
• Photochemistry
• Materials science

Background:

• Exciplexes are crucial in photocatalysis, but their dynamic behavior is complex.
• Previous static methods limited conformational sampling for exciplexes.
• Understanding exciplex emission is key for designing efficient photoredox catalysts.

Purpose of the Study:

• To develop and validate a computational protocol for modeling exciplex emission spectra.
• To investigate the conformational dynamics of oligo-p-phenylene (OPP) and triethylamine (TEA) exciplexes.
• To assess the efficiency and accuracy of excited-state ab initio molecular dynamics (AIMD) for exciplex systems.

Main Methods:

• Utilized excited-state ab initio molecular dynamics (AIMD) simulations.
• Modeled exciplexes formed by oligo-p-phenylenes (OPP) and triethylamine (TEA).
• Compared AIMD results with experimental and previous computational findings.

Main Results:

• AIMD successfully reproduced experimental emission spectra for OPP-TEA exciplexes.
• AIMD provided efficient conformational sampling, outperforming static methods.
• Intersystem crossing (ISC) was identified as a minor decay pathway for OPP3 and OPP4 exciplexes.

Conclusions:

• AIMD simulations offer an efficient and accurate method for studying exciplex dynamics and spectra.
• The protocol enhances understanding of structural flexibility and emission characteristics of photoredox catalysts.
• Findings contribute to improved design strategies for organic chromophores in photocatalytic applications.