For our purposes, we consider π -π stacking to be partially disrupted when the best-fit planes of the two monomers are inclined by at least 8 • relative to each other. If these six dimers are removed from consideration, the R 2 improves to 0.4288; see Figure showing E b vs. dipole cancellation for all the DBT, DBTO, DBF, Fluor, and MeCarb dimers. The correlation is still poorer than that for the Phen and BzQuin dimers, but is large enough to indicate that dipole cancellation is a significant factor in determining the binding energy for a given dimer conformation. The inferior correlation is likely the result of the monomers being less similar to each other than the similarity between Phen and BzQuin. In dimers of DBT, DBTO, DBF, Fluor, and MeCarb, there is greater variation in contact surface area, shape, and polarizibility, which will complicate the results, and make correlations harder to find. If the correlation is only considered within homologous series, then R 2 ranges from 0.1135 to 0.7014; see Figure in the SI.