Beyond the baseline strategy, we considered three approaches for this scenario. In the first, we set the O2 binding energy for inactive sites to 0.0 eV and trained the regression model on the full set of sites. We then ordered the active sites to search based on the predicted strongest O2 binding energy for all sites and conducted the simulated search of active sites in that order. The second and third approaches restrict the search to sites a classifier predicts to be active, and then searches those sites based on the order predicted by the regression model that was only trained on active site O2 binding energies. The distinction between the second and third approaches was in the training features used: one used all structural and electronic features available, and the other used only the structural features. The speedup ratios of each method relative to randomly sampling are shown in Figure . Despite notable differences in the model architectures, features, and accuracies on validation datasets, the performances of the models are remarkably similar. In particular, despite a significant difference in their overall accuracy, the classification step for both of the sequenced classification-regression models identified the same 14 search target active sites as active, in each case misclassifying a different one of the 15 as inactive. This indicates that the properties cause very strong O2 binding for these molecules can be predicted largely from the structure alone, and in such cases can be predicted with a good degree of certainty, diminishing the impact of electronic features and classification accuracy. In addition to model performance, Figure also depicts the molecule with the strongest O2 binding strength among all molecules considered in this study. This molecule possesses a rather small aromatic system around the active site where O2 bound, which is a feature that was common to the other molecules that bound O2 most strongly. If these molecules were converted into GCCs through addition of a diamine that was conjugated to graphite, the O2 binding strength for this subset of molecules would likely change, and this effect should be considered in future studies.