Committor of elementary reactions on multistate systems

Area of Science:

• Chemical Physics
• Computational Chemistry
• Statistical Mechanics

Background:

• The committor concept is crucial for analyzing reaction dynamics in chemical systems.
• Multi-minima systems present challenges due to multiple potential reaction pathways.
• Evaluating reaction feasibility often requires projecting dynamics onto partial reactions.

Purpose of the Study:

• To extend the committor concept to multi-minima systems.
• To define and calculate the elementary reaction committor and reactive trajectory probability densities.
• To develop visualization methods for identifying key reaction channels and nonreactive domains.

Main Methods:

• Definition and calculation of the elementary reaction committor.
• Projection of dynamics onto partial reactions for multi-minima systems.
• Development of a visualization technique for committor functions and probability densities.
• Application to a 2D Langevin dynamics model and molecular dynamics of 2-chlorobutane.

Main Results:

• Successful extension of the committor concept to multi-minima systems.
• A novel visualization method effectively identifies important reaction channels and nonreactive regions.
• Weighted energy-committor plots clarify limitations of minimal energy path and average energy concepts.
• The method accurately analyzes molecular dynamics trajectories of 2-chlorobutane.

Conclusions:

• The elementary reaction committor provides a robust framework for analyzing complex chemical reactions.
• The proposed visualization and analysis methods enhance the understanding of reaction dynamics in multi-minima systems.
• This approach offers valuable insights into reaction mechanisms and pathway identification in computational chemistry.