To demonstrate that the numerical value of corrections such as D3 cannot be equated with genuine dispersion energies, Shahbaz and Szalewicz examined this corrections in comparison to a variety of SAPT benchmarks. Figure plots several D3(BJ) corrections for Ar 2 , as parameterized for several different XC functionals, alongside SAPT2+ dispersion energies. The D3(BJ) potential curves exhibit significantly shifted minima relative to E SAPT2+ disp (R). The former behave better asymptotically, because they are based on isolated-atom polarizabilities and should recover longrange dispersion, up to any intrinsic error associated with polarizabilities obtained from TDDFT. For a fixed value of R (say, the equilibrium separation R = 3.76 Å that is indicated in Fig. ), the D3(BJ) corrections exhibit a wide range of numerical values that may be larger or smaller than the SAPT2+ dispersion energy. Clearly, the numerical value of the D3(BJ) correction cannot be equated with dispersion and may not have physical meaning. Others have reached the same conclusion in more systematic comparisons of D3(BJ) to SAPT. To avoid the inevitable intermingling of semilocal correlation and long-range empirical dispersion in the "middle-range" region (which is the length scale of typical vdW contact distances), Pernal et al. developed a "dispersionless" density functional (dlDF) by reparameterizing M05-2X using a data set from which benchmark-quality SAPT dispersion energies had been subtracted from the data. Empirical corrections can be added to that functional (dlDF+D, using Grimme's D2 form), without concern about double-counting correlation. Figure (a) demonstrates that this approach provides an accurate potential energy curve for Ar• • • Ne, much more so than the original M05-2X functional or the M06-2X functional, and also more accurate than B97+D. A similar approach has been used to develop empirical dispersion potentials to replace secondorder dispersion in SAPT0. If a dispersion correction developed for DFT is used for this purpose,