Mean-Field Ring Polymer Rates Using a Population Dividing Surface.

Area of Science:

• Computational Chemistry
• Chemical Dynamics
• Theoretical Chemistry

Background:

• Mean-field ring polymer molecular dynamics (MF-RPMD) is computationally efficient for simulating reaction rates.
• Accurate modeling of nonadiabatic state-to-state reactions requires specific trajectory configurations at the dividing surface.

Purpose of the Study:

• To develop a more accurate and efficient method for calculating reaction rates in multilevel systems.
• To incorporate the necessity of kinked ring polymer configurations into mean-field rate theory.

Main Methods:

• Introduction of a population difference coordinate.
• Modification of the reactive flux expression to include only kinked configurations.
• Testing the kMF-RP approach on linear vibronic coupling models.

Main Results:

• The new kMF-RP rate approach is efficient to implement.
• The method demonstrates quantitative accuracy across various models.
• Accuracy is maintained over a wide range of driving forces, coupling strengths, and temperatures.

Conclusions:

• The kMF-RP method provides an efficient and accurate way to simulate reaction rates in complex systems.
• This approach successfully integrates the importance of kinked configurations for nonadiabatic dynamics.
• The method is validated for diverse chemical and physical conditions.