Other reaction types deviate more strongly, with Sarathy et al. estimating epoxy formation around a million times slower than this work suggests. In the Sarathy mechanism, these rates originate from rate rules based on alkane fuels; such reactions have an activation energy of around 92 kJ/mol, which is substantially higher than activation energies given from quantum calculations for ethane oxidation, between 50-70 kJ/mol. In addition, the rates in Sarathy et al. are 2-3 orders of magnitude slower than those recommended by a more recent structure-activity relationship. The barrier heights for epoxy formation reactions from isobutanol in this present work and other studies are also approximately 21 kJ/mol lower than those reported for alkane and ethanol oxidation. The large differences between the estimates in Sarathy et al. and those in this work can be attributed to the use of older structure-activity relationships and/or differences between alkane chemistry (on which the Sarathy et al. rate rule is based) and the chemistry of isobutanol oxidation.