Absent CP correction (Fig. ), the minimum-energy separation of the dimer changes as a function of basis set, increasing from 3.50 Å in double-ζ basis sets to 3.75 Å in larger basis sets. The potential curve is also much shallower in the larger basis sets, consistent with toolarge values of ∆E int due to BSSE, and the effect is large than it was for the smaller S66 dimers. The def2-SVP and def2-SVPD basis sets overestimate ∆E int by 7.0 and 5.0 kcal/mol, respectively, as compared to the def2-QZVPD value. On the other hand, triple-ζ results are essentially converged to the CBS limit.