Node features corresponding to the number of bonded CHON atoms were also directly featurized, even though this is an implicit feature that might be learned from the convolution. The novel edge features include a set of binary features corresponding to whether the bond was broken, formed, if the bond order changed, or was unchanged. These features are necessary to use the union of the reactant and product graphs as the inputted graph topology to the model. For example, the reactant may have some edges with bond order zero, because these might only exist in the product, but it is nonetheless potentially useful for the model to mix information along these edges given the fact that a bond forms or breaks between such atoms in the reaction.