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Fragment-Based Ab Initio Molecular Dynamics Simulation for Combustion.

ABSTRACT: 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.

SUBMITTER: Cao L

PROVIDER: S-EPMC8197069 | biostudies-literature |

REPOSITORIES: biostudies-literature

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TAO-DFT-Based <i>Ab Initio</i> Molecular Dynamics.

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Molecular-scale modeling of light emission by combustion: An ab initio study.

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Interaction of HIV-1 aspartic protease with its inhibitor, by molecular dynamics and ab initio fragment molecular orbital method.

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Ab Initio Molecular Dynamics Simulation Study on the Stereo Reactions between Atomic Oxygen Anion and Methane.

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Project description:Electrolysis is a potential candidate for a quick method of wastewater cleansing. However, it is necessary to know what compounds might be formed from bioorganic matter. We want to know if there are toxic intermediates and if it is possible to influence the product formation by the variation in initial conditions. In the present study, we use Car-Parrinello molecular dynamics to simulate the fastest reaction steps under such circumstances. We investigate the behavior of amino acids and peptides under anodic conditions. Such highly reactive situations lead to chemical reactions within picoseconds, and we can model the reaction mechanisms in full detail. The role of the electric current is to discharge charged species and, hence, to produce radicals from ions. This leads to ultra-fast radical reactions in a bulk environment, which can also be seen as redox reactions as the oxidation states change. In the case of amino acids, the educts can be zwitterionic, so we also observe complex acid-base chemistry. Hence, we obtain the full spectrum of condensed-phase chemistry.

| S-EPMC7699423 | biostudies-literature

Meteorite Impact-Induced Rapid NH<sub>3</sub> Production on Early Earth: Ab Initio Molecular Dynamics Simulation.

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