Although many-body effects are sometimes invoked as a neglected source of dispersion energy, analysis using methods like XDM have generally found that pairwise interactions account for the bulk of the dispersion interaction, while non-additive many-atom dispersion is slightly repulsive in general and only accounts for a very small fraction of the total dispersion energy. Finally, the widespread practice of applying a switching function to terminate the Lennard-Jones interaction at a moderate distance (e.g., 12 Å) has also caused the force field C 6 dispersion coefficients to be exaggerated. This truncation is also used when the force field is parameterized, so the parameterization procedure of some force fields tends to assign a spuriously large C 6 coefficient to the parameterized atoms to compensate for the neglected long-range dispersion interactions (although a correction is made for this approximation in some force fields). Fisher et al. found that the enthalpies of vaporization of liquids in the Virtual Chemistry test set were systematically overestimated when the long-range dispersion interactions were calculated, which is consistent with our conclusion that the dispersion coefficients for these force fields are larger than they should be on physical grounds. For homogeneous systems, there are methods of correcting for the neglect long-range dispersion interactions without explicitly calculating them using a lattice-summation method, although this has not been used universally in force field parameterization. The redevelopment of force fields to include long-range dispersion interactions would likely result in smaller C 6 dispersion parameters. Lennard-Jones parameters for bromine are not optimal. The bromine dispersion coefficients for the reparameterized force field were closer to the XDM values (206.7 a.u. and 163.1 a.u.