Thermochemistry Prediction and Automatic Reaction Mechanism Generation for Oxygenated Sulfur Systems: A Case Study of Dimethyl Sulfide Oxidation

Automatic mechanism generation is a powerful approach to understanding complex chemical mechanisms. Here we describe the expansion of an open source mechanism creating software, the Reaction Mechanism Generator or RMG, to oxygenated sulfur systems. This principally involved the expansion of thermochemistry estimation techniques for higher valence oxygenated sulfur molecules. As a demonstration of this new tool, we present an automatically generated mechanism describing the oxidation of dimethyl sulfide. This mechanism is then compared to several experimental studies of dimethyl sulfide oxidation. This case study provides insight into the transformation of sulfur species in the atmosphere, especially the formation pathways of sulfoxides, sulfones, and sulfur dioxide. However, the applications of the newly enhanced mechanism generation tool extend far beyond this single system with obvious use in understanding a variety of atmospheric, petrochemical, and other industrial chemistries.