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Lagrangian descriptors in dissipative systems
Andrej Junginger1, Rigoberto Hernandez1
1Center for Computational and Molecular Science and Technology, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332-0400, Georgia. hernandez@gatech.edu.
Physical Chemistry Chemical Physics : PCCP
|June 22, 2016
Summary
This study introduces a weighted Lagrangian descriptor method to accurately model reaction dynamics in time-dependent systems with dissipation. The approach preserves crucial phase space structures lost in non-weighted methods.
Area of Science:
- Chemical Dynamics
- Theoretical Chemistry
- Statistical Mechanics
Background:
- Reaction dynamics in time-dependent systems are challenging to resolve.
- Transition state trajectories are key to understanding reaction pathways.
- Previous methods for constructing these trajectories did not account for dissipation.
Purpose of the Study:
- To extend the Lagrangian descriptor method for systems with dissipation.
- To develop a robust approach for analyzing time-dependent reaction dynamics under dissipative conditions.
- To preserve essential phase space structures in the presence of friction.
Main Methods:
- Minimization of Lagrangian descriptors to identify transition state trajectories.
- Integration of trajectories in both forward and backward time.
- Introduction of a novel weighting scheme for the Lagrangian descriptor to account for friction.
- Application to thermal Langevin dynamics.
Main Results:
- The standard Lagrangian descriptor method loses phase space structure in dissipative systems due to friction.
- The proposed weighted Lagrangian descriptor successfully preserves essential phase space structures.
- The method provides a more accurate description of reaction dynamics with dissipation.
Conclusions:
- The weighted Lagrangian descriptor is a powerful tool for studying dissipative reaction dynamics.
- This method overcomes limitations of previous approaches in handling friction.
- It enables a more complete understanding of complex chemical reactions.
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