Formation mechanisms of the component composition for thin films and aqueous solutions of symmetric cyanine dyes

The equilibrium component composition of films and aqueous solutions of symmetric cyanine dye was studied by the absorption spectroscopy. Films as well as aqueous solution contain several monomeric components (different isomers) and aggregate forms (dimers and J-aggregates). The observed components are the ionic pairs. The relative concentrations of the components depended on the structure of dye (anion, bulk and electron-donation ability of terminal groups) and its concentration.