where S i is the kinetic sensitivity with respect to reaction i, k i,original is the rate coe cient of reaction i, k i,perturbed is the rate coe cient of reaction i after perturbation, X original represents the value of a descriptor (e.g.CH 4 conversion), and X perturbed represents the descriptor value after the rate of reaction i is perturbed. The thermodynamic sensitivity was calculated by increasing the enthalpy of one adsorbate by 0.05 eV at a time and comparing the descriptor di↵erence at a position on the catalyst. It is important to note that the enthalpy change is not modified proportionally (e.g. by 1%) because the definition of zero enthalpy is arbitrary.