Photoprotolytic Dissociation in Micellar Solutions

Photoprotolytic reactions in micellar solutions were systematically studied by the authors of the present review with coworkers [15, 16, 66, 120-122]. Effective dissociation rate constants ki for a set of hydroxyaromatic compounds in anionic, cationic and uncharged micelles were determined from the dependence of fluorescence quantum yields on the concentration of micelles [Eq. (22)] or on the concentration of acid [Eq. (49)]. The latter method was also used for determining the effective equilibrium constants and effective rate constants of the reverse protonation reaction [Eq. (49)]. The data obtained are presented in Table 3. 

The difference of free energies of protolytic reactions in the micellar phase AG and in aqueous solution were determined in the pseudophase model or in the microscopic model by the ratio of distribution coefficients (binding constants) of the initial acid ( ) and its anions ( ) and protons ( )  

It is convenient to exclude the distribution coefficient of protons q and to define pK in such a way that it is related to the pH value of the aqueous phase  

The ratio i determined from Eq. (49) is not identical to the equilibrium constant. For the cases la-2b discussed in Sect. 1.2.4  

2-Naphthol 2-Naphthol-8-sulfonate 2-Naphthol-6-sulfonate 1.7- Dihydroxynaphthalene 2.7- Dihydroxynaphthalene 2-Anthrol 0.1  

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