Table : Various datasets used in this work. The purpose of the "Number of compounds/topologies/configurations" columns is to give a sense of the diversity of structures in each of the datasets. "Number of configurations" refers to the total number of 3D geometry entries in the dataset. Multiple 3D geometries may have the same "topology" or "connectivity", e.g. different conformers of the butane molecule are classed as having the same "topology". Finally, the datasets that contain both closed-and open-shell structures may have both, the parent closed-shell molecule and, possibly multiple, open-shell radicals derived from the parent molecule by removing an appropriate hydrogen atom. Because their structures significantly overlap, "Number of compounds" counts the geometries of the parent molecule and derived open-shell structures as the same "compound". The COMP6 benchmark was first described by Smith & co. In all cases, only the [C,H,O]-containing structures were used.