One of the most important purposes in molecular technologies is the preparation of supramolecular structures by self-assembling processes. The aromatic molecules self-associate mainly in π-π stacked structures with an aggregate size distribution determined by the association equilibrium constants. A general expression for the equilibrium constants K(n,m) which govern the self-association of two aggregates with n and m monomers respectively has been obtained. The model predicts also the concentrations of free monomers, the concentrations of n-mers, and the total concentration of aggregates. (1)H NMR experiments have been used to illustrate the applicability of the proposed model in a particular case: π-stacking self-association of ciprofloxacin in solution.

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http://dx.doi.org/10.1021/jp3034215DOI Listing

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