Again, very little change in force field accuracy is observed, with density errors in the range 0.02-0.03 g/cm 3 and heat of vaporisation errors in the range 0.6-0.8 kcal/mol. This is broadly in agreement with previous observations, which showed a strong dependence of condensed phase properties on the polarity of the charge model for a fixed set of Lennard-Jones parameters, but much less sensitivity when the Lennard-Jones parameters are tuned for consistency with the charges. Table shows that the R f ree i parameters in run 2a tend to be lower than the others, which indicates that the minimum of the Lennard-Jones interaction should be closer to the atom for the less-polarised charge model. Compared to vacuum, we found that molecular dipole moments are scaled by a factor of 1.10x ( = 2) and 1.22x ( = 20), on average, indicating that a suitable range of condensed phase polarisation has been captured in these force field models by tuning the dielectric of the background implicit solvent (Figure ).