Nitromethane Decomposition via Automated Reaction Discovery and an Ab Initio Corrected Kinetic Model

J Phys Chem A. 2021 Feb 25;125(7):1447-1460. doi: 10.1021/acs.jpca.0c09168. Epub 2021 Feb 11.

Abstract

We explore the systematic construction of kinetic models from in silico reaction data for the decomposition of nitromethane. Our models are constructed in a computationally affordable manner by using reactions discovered through accelerated molecular dynamics simulations using the ReaxFF reactive force field. The reaction paths are then optimized to determine reaction rate parameters. We introduce a reaction barrier correction scheme that combines accurate thermochemical data from density functional theory with ReaxFF minimal energy paths. We validate our models across different thermodynamic regimes, showing predictions of gas phase CO and NO concentrations and high-pressure induction times that are similar to experimental data. The kinetic models are analyzed to find fundamental decomposition reactions in different thermodynamic regimes.