The CMC of a binary mixture of surfactants 1a and 1b can be expressed as a function of the CMC’s of the constituent pure sur-factants as follows [9]:
If Eqs. (5)–(7) give the real values of the intermolecular inter-action parameter, the composition of the mixed micelles and the activity coefficients of surfactants in the micelles, then from Eq.(8), the same values of CMC of the TX-100 and CTAB mixture asthe measured ones should be obtained. Introducing to Eq. (8) the activity coefficients of surfactants calculated from Eqs. (6) and (7)(Figs. S14 and S15), we obtained the same CMC1values as those measured.