SMIRNOFF assigns parameters to molecules separately by type (i.e. bonds, angles, and torsions are treated independently) with explicit treatment for bond order which differs from the atom-type approach used by the other force fields in this study . It is possible this change in chemical perception can help account for the change in treatment of these systems. QM data on these molecules will be useful for future iterations of the SMIRNOFF force field, which are already in development. Table . Selected Pair Enriched Checkmol Descriptor Pairs in the Set. Shown are the pair enrichment factors corresponding to selected descriptor pairs, calculated using Equation . The three descriptor pairs shown are the three pairs that yielded the highest pair enrichment factor in the set.