For IBU the obtained ∆G 0 bind are 1.4 and -0.6 kcal/mol for up and down, respectively, and for KET they are 1.2 and 1.7 kcal/mol, respectively. The free energies of binding obtained by applying eq 4 for the DS values shown in Figure and appropriately scaled with the relative abundances are presented in Table . Here we observe, that the linear model performs well for up orientations for both IBU and KET with deviations less than or equal to 0.2 kcal/mol.