Gaussian-theory predictions of proton transfer to water of phenol and 3-chlorophenol: resolution of an apparent difficulty

Gaussian-theory calculations, G1, G2 and G3, are in good agreement with experiment for the proton transfer reaction free energy from phenol and 3-chlorophenol to water. This is in contrast to earlier calculations at the G1 and G2 levels that had indicated errors of 600–750 kJ mol−1. There are no apparent artifacts of MP4-level basis set corrections in these calculations. There is no evidence that these theories perform any less well when applied to aromatic compounds than systems for which they have been successfully applied previously.