Generalised Marcus theory for multi-molecular delocalised charge transfer.

Area of Science:

• Chemical Physics
• Physical Chemistry
• Molecular Dynamics

Background:

• Marcus theory traditionally models charge transfer between single donor and acceptor molecules.
• Extending this to multiple molecules requires computationally expensive supermolecular calculations.
• Understanding aggregate contributions to charge transfer is challenging with current methods.

Purpose of the Study:

• To develop a generalized Marcus theory applicable to charge transfer involving molecular aggregates.
• To simplify calculations by focusing on constituent molecules and their couplings.
• To investigate the impact of charge delocalization on charge transfer rates.

Main Methods:

• Formulating a generalized Marcus theory for charge transfer between molecular groups.
• Analyzing the influence of constituent molecular properties and inter-molecular couplings.
• Deriving closed-form equations for charge transfer dynamics.

Main Results:

• Demonstrated that charge transfer between molecular groups can be described without supermolecular calculations.
• Identified 'supertransfer' and 'subtransfer' phenomena due to charge delocalization.
• Showed that tuning energy levels and reorganization energies can enhance rates beyond single-donor/acceptor systems.
• Described bridge-mediated charge transfer between delocalized aggregates.

Conclusions:

• The generalized theory provides a computationally efficient and insightful approach to molecular charge transfer.
• Charge delocalization within donor or acceptor aggregates significantly modulates transfer rates.
• The framework offers qualitative understanding of charge dynamics in complex molecular systems.