The Arrhenius rate expression is not a↵ected by species enthalpy, so the @k/@H j term of Equation 15 is zero when using the original model with Arrhenius rates. On the contrary, reaction enthalpy is considered in the BMA rate expression, and because reaction enthalpy is a function of species enthalpy, the (@X/@k)(@k/@H j ) term in Equation 15 is included. Thus, models with BMA expressions will give more realistic thermodynamic sensitivity results than models with only Arrhenius expressions. It is worth noting that because all our models use reversible reactions, Cantera ensures thermodynamic consistency by deriving the equilibrium constant from G rxn , and so the reverse rate coe cients depend on reaction enthalpy H rxn in both CMPO and CMPO-BMA models.