All-Atom Photoinduced Charge Transfer Dynamics in Condensed Phase via Multistate Nonlinear-Response Instantaneous...

Area of Science:

• Computational Chemistry
• Photochemistry
• Materials Science

Background:

• Photoinduced charge transfer (CT) is crucial for solar energy conversion but difficult to simulate at the all-atom level.
• Traditional Marcus theory cannot account for nonequilibrium effects in nuclear preparation during CT.
• Instantaneous Marcus theory (IMT) and its nonlinear-response formulation address these nonequilibrium effects for two-state systems.

Purpose of the Study:

• To extend the nonlinear-response IMT for simulating photoinduced CT in systems with multiple electronic states.
• To demonstrate the enhanced IMT method using a carotenoid-porphyrin-fullerene triad in tetrahydrofuran.
• To evaluate the method's ability to capture nonequilibrium nuclear effects in CT dynamics.

Main Methods:

• Developed a multistate nonlinear-response IMT framework.
• Employed all-atom molecular dynamics simulations to obtain energy gap time correlation functions.
• Calculated time-dependent averages and variances of energy gaps for IMT input.

Main Results:

• The multistate IMT successfully captured significant nonequilibrium effects from initial nuclear state preparation.
• Multistate IMT predicted population dynamics substantially different from, and more accurate than, traditional Marcus theory.
• The enhanced IMT showed better agreement with all-atom nonadiabatic mapping dynamics compared to Marcus theory.

Conclusions:

• The multistate nonlinear-response IMT provides a practical and cost-effective strategy for studying complex condensed-phase CT dynamics.
• This method accurately accounts for crucial nonequilibrium nuclear effects, offering improved simulation capabilities.
• The developed framework is valuable for advancing research in solar energy conversion and other CT-driven processes.