The SCS-CC2/CBS(3,4) reference curve for the benzene excimer predicts a potential well minimum with a D e of 13.65 kcal/mol at r e 2.97 Å which the tested double hybrids both over and underestimate depending on the method (Figure ). Associated absolute deviations in D e range from 0.01 [ωB2GP-PLYP] to 7.87 [ωPBEPP86] kcal/mol (0.1 to 58 % error) and in r e range from 0.01 to 0.15 Å. Other than SCS-RSX-QIDH, scaled variants predict weaker binding than the unscaled functional, with SCS variants predicting stronger binding (larger D e and smaller r e ) than SOS variants. This is expected due to less perturbative, non-local correlation being calculated by SCS and SOS methods.