Fragment-Based Ab Initio Molecular Dynamics Simulation for Combustion.

Molecules

School of Chemistry and Molecular Engineering, Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, East China Normal University, Shanghai 200062, China.

Published: May 2021

We develop a fragment-based ab initio molecular dynamics (FB-AIMD) method for efficient dynamics simulation of the combustion process. In this method, the intermolecular interactions are treated by a fragment-based many-body expansion in which three- or higher body interactions are neglected, while two-body interactions are computed if the distance between the two fragments is smaller than a cutoff value. The accuracy of the method was verified by comparing FB-AIMD calculated energies and atomic forces of several different systems with those obtained by standard full system quantum calculations. The computational cost of the FB-AIMD method scales linearly with the size of the system, and the calculation is easily parallelizable. The method is applied to methane combustion as a benchmark. Detailed reaction network of methane reaction is analyzed, and important reaction species are tracked in real time. The current result of methane simulation is in excellent agreement with known experimental findings and with prior theoretical studies.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8197069PMC
http://dx.doi.org/10.3390/molecules26113120DOI Listing

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