Imaginary-time open-chain path-integral approach for two-state time correlation functions and applications in charge...

Area of Science:

• Quantum dynamics
• Physical chemistry
• Computational chemistry

Background:

• Quantum time correlation functions (TCFs) are crucial for nonadiabatic processes, including charge transfer (CT).
• Existing methods for evaluating two-state TCFs have limitations.

Purpose of the Study:

• To propose and validate an imaginary-time open-chain path-integral (OCPI) approach for calculating two-state symmetrized TCFs.
• To accurately describe nonadiabatic dynamical processes like charge transfer.

Main Methods:

• Developed an imaginary-time OCPI method based on a single-state approach.
• Transformed path variables for analytical integration.
• Employed importance sampling with open path-integral molecular dynamics.
• Calculated Fermi's golden rule CT rate constant using a spin-boson model.

Main Results:

• The imaginary-time OCPI method accurately computes two-state symmetrized TCFs and rate constants.
• The method demonstrates accuracy comparable to real-time linearized semiclassical and analytical results.
• The OCPI scheme effectively captures electronic quantum coherence and nuclear quantum effects.

Conclusions:

• The proposed imaginary-time OCPI approach provides an accurate and efficient method for studying two-state quantum dynamics.
• This method is valuable for understanding complex processes like charge transfer in quantum systems.