We observe that the limiting step at lower protonation energies is the reduction reaction Mo NH + Mo N 2 H 2 reactions in the GA, since all the cases where the protonation energy is negative the reduction energy is positive. However, we note that even though there appears to be introduced barriers for the Mo NH + 3 Mo NH 3 reaction, the overall energy profile of the last 3 reaction steps of Schrock cycle (Mo NH + 3 Mo N 2 ) is better for all three top scoring catalysts (Cat1,2,3) in It would be relevant to explore GA objectives where the target protonation value is a range between 0 and -5 kcal/mol instead of as negative as possible to find a compromise between a negative protonation energy and a low barrier Mo NH + 3 Mo NH 3 reaction. Given the complexity of the task, the GA performed extremely well at lowering the protonation energy, while preventing significant barriers for the remaining 14 steps in the cycle. Mo N 2 H. The scaling relations used to construct this figure are found the SI (Figure ). pds is the potential determining step.