Overall, the errors with HF are very similar to those observed in the case of DFT, in particular for the two-body expansion. With the db-MBE(2), the errors are between 0.8 kJ/mol and 6. slight mismatch between the density-based correction (which makes use of an approximate nonadditive exchange-correlation functional) and the supermolecular HF calculation, which does not include correlation effects.