With the notable exception of the Tang-Toennies damping function, each of the various damping procedures performs similarly with errors of about 2%. The Tang-Toennies function, however, damps E disp to such an extent that the dispersion-corrected method is no better than plain HF theory without any dispersion correction at all! In the absence of a dispersion correction, or when the Tang-Toennies damping function is used, HF theory underbind the IL195×8 complexes by an average of almost 7 kcal/mol, as shown in Fig. . In fact, this underbinding was the original motivation for replacing the exponential in the Tang-Toennies damping function with a Gaussian function. The "no dispersion" method is conventional HF theory whereas other entries are HF+D(EFP) with various damping functions. In two cases, the maximum error exceeds 8.5 kcal/mol and is cut off in this graph.