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Inertial dynamic effects on diffusion-influenced reactions: Approach based on the diffusive Cattaneo system
Sangyoub Lee1, Sergey D Traytak1
1Department of Chemistry, Seoul National University, Seoul 08826, South Korea and N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 4 Kosygina St., 119991 Moscow, Russian Federation.
The Journal of Chemical Physics
|May 23, 2023
Summary
Inertial dynamics slow down diffusion-influenced reactions, affecting both bulk and geminate recombination rates. This inertial effect is particularly noticeable at short times and can be experimentally observed in geminate pair survival probabilities.
Area of Science:
- Chemical Kinetics
- Physical Chemistry
- Reaction Dynamics
Background:
- Diffusion-influenced reactions are fundamental in chemical processes.
- Previous models often neglected inertial dynamics, limiting accuracy for fast reactions.
- Understanding inertial effects is crucial for reactions with finite reactivity.
Purpose of the Study:
- To investigate inertial dynamic effects on diffusion-influenced reactions.
- To analyze the impact of finite reactivity alongside inertial dynamics.
- To derive analytical expressions for bulk and geminate recombination rates.
Main Methods:
- Solving the linear diffusive Cattaneo system with a reaction sink term.
- Developing analytical expressions for recombination rates.
- Analyzing the short-time behavior of reaction kinetics.
Main Results:
- Inertial dynamics were found to retard both bulk and geminate recombination rates at short times.
- Explicit analytical expressions for these rates were derived.
- A distinct inertial effect on the survival probability of geminate pairs at short times was identified.
Conclusions:
- Inertial dynamics significantly influence reaction kinetics, especially at short timescales.
- The findings extend previous analytical studies by including finite reactivity.
- The predicted effects on geminate pair survival probability offer potential for experimental validation.
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