• Reactions involving a charge change |∆q| > 1 Motivations for each of these filters, along with examples, are provided in the Supplementary Information. Like species filters, the reaction filters can be easily modified and extended by end users to suit a broad range of chemical applications. Of course, removing filters will yield a larger final collection of reactions. We note that for the size of the species collection presented in this work, some filters are necessary to obtain a tractable number of reactions in the final collection. For thousands of species, it is further necessary to filter reactions in parallel and for each filter to be computationally efficient in order to allow filtering to complete in a reasonable amount of time (hours to days).