Two reaction classes have been studied computationally including the pyrolysis of various components of airplane fuels, such as decane, dodecane, butylbenzene isomers, and JP-10 (exo-tetrahydrodicyclopentadiene), and oxidation of a group of molecules belonging to the class of Polycyclic Aromatic Hydrocarbons (PAHs). Investigation of both reaction classes have been performed using ab initio quantum chemistry methods with the Gaussian 09 and MOLPRO programs at various levels of theory. Initially, Potential Energy Surfaces (PES) were generated at the G3(MP2,CC)/B3LYP/6-311G** level of theory for various radicals involved in the reactions as reactants, intermediates, transition states, and products. The next step was to perform RiceRamsperger-Kassel-Marcus (RRKM) / Master Equation calculations in order to calculate rate constants and branching ratios of different products at various temperatures and pressures characteristic for combustion flames. All calculations were then compared with previous works on similar systems available in the literature. The results of these simulations along with previous data were then used to formulate guidelines for the pyrolysis and oxidation patterns of larger and more complex systems, in order to achieve a better understanding of the pathways to the end products in airplane jet engines.
