We briefly review the graphically-defined model reaction template and benchmarking performed here before giving detailed descriptions in the following sections. The prediction of a transition state using a model reaction involves up to three steps: reaction class identification, model reaction generation and characterization (if not already available), and transition state (TS) initial guess generation (Fig. ). In scenarios where the user wants to simply use the activation energy of the model reaction in place of the true activation energy (based on our benchmarks this is often an excellent approximation), only the first two steps would be required. The down-conversion from large reaction instances to simpler model reactions is shown in Figures , respectively, and a step-by-step illustration from model reaction generation through to TS initial guess generation is provided in Figures . In brief, the graphically defined model reaction is automatically determined from the changes in the bonding structure between the reactant(s) and product(s).