For a site-agnostic analysis of the building blocks, we calculate the z-scores for the 18 building blocks as shown in Fig. . For this figure, we look at the top 5% of the catalysts (w.r.t. ∆G) for each of the six reactions, and evaluate the contribution (presence/absence in the catalyst molecule) of each building block in this subset vs their contribution in the remainder of the library. For catalyst sites A and B, we see a high positive as well as high negative correlation, whereas for sites C and D, the correlation goes from moderately positive to weakly neg-FIG. : A comparison of the performance of machine learning models trained using various 2-D and 3-D descriptors for predicting the ∆G r of all six dehydrogenation steps simultaneously. The y-axis corresponds to the sum of the mean absolute errors (test set) of the six predictions for each catalyst molecule. The blue, orange, green, and red lines for each descriptor refer to the four types of optimized geometries used for generating the 3-D descriptors.