The first, "Molecular Fingerprint," version uses a sum readout function before reducing the atomic features to a single value, which effectively produces a set of features that describes the entire molecule. The "Atomic Contribution" version reduces the atomic features to a single scalar value before summing over all atoms, which approximates each atom having an additive contribution to solvation energy. Full details of the models are available in the Supplementary Information, on the GitHub page associated with this work and on the Materials Data Facility.