Extracting the mechanisms and kinetic models of complex reactions from atomistic simulation data
Yanze Wu1, Huai Sun1, Liang Wu1
1School of Chemistry and Chemical Engineering, Materials Genome Initiative Center, and Key Laboratory of Scientific and Engineering Computing of Ministry of Education, Shanghai Jiao Tong University, Shanghai, China, 200240.
Journal of Computational Chemistry
|February 26, 2019
Summary
This study presents a new method to determine chemical reaction mechanisms and kinetic models from atomistic simulations. The approach simplifies complex networks for accurate chemical reaction engineering and design.
Area of Science:
- Chemical Engineering
- Computational Chemistry
- Reaction Kinetics
Background:
- Deriving reaction mechanisms and kinetic models from atomistic simulations is crucial but challenging for chemical reaction engineering.
- Accurate kinetic models are essential for designing and optimizing chemical processes.
Purpose of the Study:
- To develop a novel methodology for determining reaction mechanisms and kinetic models from atomistic simulation data.
- To simplify complex reaction networks into skeletal networks suitable for kinetic modeling.
- To validate the derived kinetic models against simulation and experimental data.
Main Methods:
- A three-component approach: (1) identifying species/reactions and calculating rate constants, (2) reducing complex networks to skeletal ones, and (3) validating full and skeletal models.
- Application of the methodology to hydrogen combustion simulation data.
- Statistical calculation of reaction rate constants and deterministic model validation.
Main Results:
- Successfully derived a full reaction network (69 species, 256 reactions) and a reduced skeletal network (9 species, 30 reactions) for hydrogen combustion.
- Both full and skeletal kinetic models accurately represented the simulation data.
- Essential elementary reactions and rate constants showed favorable agreement with experimental findings.
Conclusions:
- The developed methodology effectively determines chemical reaction mechanisms and kinetic models from atomistic simulations.
- Network reduction simplifies complex systems for practical kinetic modeling without sacrificing accuracy.
- The approach provides a reliable tool for chemical reaction engineering and design, validated by experimental data.
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