It is worth noting that E CT as defined by the second-generation ALMO-EDA2 method does appear to have a well-defined CBS limit, as a result of a new definition of E CT as compared to the first-generation ALMO-EDA1. Even for the second-generation EDA, convergence is slow and not complete until aug-cc-pV6Z, with an 11 kcal/mol difference between double-and sextuple-ζ. That is less variability, however, as compare to ALMO-EDA1, where aug-cc-pV6Z results for the same borazane complex do not appear to have converged. The SAPT-cDFT value of E CT is considerably smaller than the ALMO-EDA2 value, which has been observed previously and attributed to a failure by cDFT to fully inhibit CT. 163 An alternative explanation is that the decision to use a pseudocanonicalized dimer basis for SAPT (Section 1.2.1) puts some intermolecular CT effects into the monomer wavefunctions, 32 classified as electrostatics. In contrast, ALMO-EDA uses the eponymous, fragment-localized ALMO basis, leading to larger CT energies. This hypothesis is at least consistent with the fact that Eq. ( ) affords smaller CT energies, as compared to ALMO-EDA2, even in double-ζ basis sets where |E (2) CT | is largest. The SAPT-cDFT definition of E CT affords what we believe to be a correct periodic trend for complexes M + • • • C 6 H 6 involving alkali cations [Fig. ]. Specifically, we expect the magnitude of E CT to decrease rapidly with ion-molecule distance, due to exponential decay of the monomer wavefunctions. For the optimized geometries that are used in Fig. (a), that distance is largest for K + and smallest for Li + , and the SAPT-cDFT scheme predicts that