The recently published most complete set of thermodynamical data on self- and hetero-complexation of aromatic molecules measured under comparable conditions of experiment was analysed with an aim of getting insight into contribution of various entropic factors to π-stacking in aqueous solution. It was found that the experimental entropy change on π-stacking is determined by counterbalancing effect of two principal factors, viz . the hydrophobic interaction (positive contribution) and the loss of degrees of freedom (negative contribution), modulated by electrostatic contribution. The mixing entropy contribution originating from the overall ordering of system due to π-stacking complexation is zero.
self-assembly, hetero-complexation, mixing entropy, entropic contribution
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