Diffusion in a Micellar Solution

Difffusion in a micellar solution is characterized by structural changes. There has been some discussion on whether these changes affect diffusion. A successful model in this area makes an assumption that its effect is important, which goes against the very large rate constants in the micellization-demicellization kinetics which would suggest instantaneous equilibration (local equilibrium). Here, an asymptotic expansion has been put together to show that both local equilibrium and significant micellization-demicellization activity are compatible. Thus, if one looks at concentrations alone they appear to be governed by local equilibrium, but if one looks at the fluxes, then small lack of local equilibrium cannot at all be ignored. The exception to this occurs in the immediate vicinity of cmc. Some experimental results are introduced to show that the present approximations are allowed only in the case of small perturbations from equilibrium. The case of tracer/NMR self-diffusion coefficient is solved successfully using this approach