Due to its ubiquity in molecular modelling, there are many water force field models available, including LJ-based force fields with various parameterisations, as well as more sophisticated functional forms . Figure shows the form of some typical non-bonded interaction potentials between two water oxygen atoms (excluding electrostatics). As discussed, a DE-based three-point water model (DE-TIP3P) has already been developed, by fitting the α and β parameters of eq 2 to reproduce the experimental water density and oxygen-oxygen distances at a single temperature . The resulting DE-TIP3P potential is similar in shape to that of the widely used TIP3P LJ model (Figure ). A number of recent water models have included a much wider range of experimental data in their training, facilitated by automated least-squares optimisation of physical properties with respect to the force field parameters in the ForceBalance software. Figure shows a LJ-based four point model trained in this way (TIP4P-FB) , as well as a water model that uses a Buckingham-6-8 (B68) non-bonded potential . The latter model (Supporting Information S1) has a more physically-motivated functional form than the LJ potential , but is more difficult to fit (many more tunable parameters) and is computationally expensive (a damping function is required to avoid instability close to r = 0).