Parameters for the simple restraint flat bottom potential. System1, system2 and system3 are βCD–Ethyl p-tolylacetate, βCD–R-(−)-Mandelic acid and βCD–Methyl 2anilinoacetate systems, respectively. δ is a tolerance (Å ) for the flat bottom potential of the distance between the receptor and the ligand for center of mass. The force constant kr is 5.0 kcal/(mol Å2) for all systems. δθ is a tolerance (degree) for the flat bottom potential of the angle is defined between two vectors, which indicate orientations of a ligand and a receptor The force constant kθ is 5.0 kcal/(mol rad2). The vectors of Ethyl p-tolylacetate and R-(−)-Mandelic acid, Methyl 2-anilinoacetate are defined by C11→C10, C11→C8 and C11→C10, respectively.