The present calculations use DFT and semi-empirical quantum chemistry but extension to correlated wave function models can be envisaged. Even for DFT calculations, our goal is to reach the basis-set limit. For that purpose, the widely-used "fragment molecular orbital method" (FMO) is inadequate. As applied to protein-ligand interaction energies, FMO is tantamount to MBE (2) with an electrostatic embedding scheme that is known to be unstable in large basis sets. Much of the FMO literature on drug discovery is focused on pairwise analysis of interaction energies, rather than the absolute value of ∆E int , but for ML applications we desire a scheme that is robust enough to target ∆E int itself.