Notably, the addition of diffuse functions to def2-SVP significantly increases the convergence errors for both functionals. This behavior was also observed for coronene dimer (Section 3 .2), where it was explained in terms of the basis-set convergence properties of the dispersionbound subset of the S66 complexes. Consistent with those examples, here we find that CP correction significantly insulates the results against this effect. With CP correction, the def2-ha-SVP basis set (in which hydrogen atoms do not have diffuse functions) performs very similarly to the fully-augmented def2-SVPD, although results in the minimally-augmented def2-ma-SVP basis set are noticeably different. This suggests def2-ha-SVP (with CP correction) as a low-cost choice for large systems, in which convergence errors have been reduced to 1 kcal/mol with respect to the DFT/CBS limit. This basis is defined for most of the periodic table, whereas 6-31+G* is only defined for elements up to argon.