We decomposed the FES (global free-energy, ∆G, in black) into the enthalpic and entropic terms, obtaining respectively the red (∆H) and blue (-T∆S) curves of Fig. (top: the sum of red and blue curves gives the free-energy, in black). The ∆H profile (red) shows two minima in correspondence of the termini of the rotaxane. In those positions the macrocycle interacts with the rest of the rotaxane both via H-bonding with the benzimidazolium sites and via π-π stacking with the stoppers (as shown in Fig. : topmost inset on the right), thus maximizing the solute-solute interactions in the system. The green curve of Fig. (bottom)