We choose to calculate the overall score as the product of the two normalised objectives, the energy-dependent term and the synthesizability penalty so that an optimal solution can only be found when both objectives are satisfied since we are not interested in high synthesizable molecules that do not perform well as catalysts or molecules that are calculated to perform well as catalysts but are not synthesizable or show uncommon structural motifs. This is achieved by using the product as shown in Equation , compared to, for example, a sum of the two terms.