Experimental evidence of a crossover in critical behaviour of water-in-oil microemulsions

Abstract

An extensive static and dynamic light-scattering experiment on a water-in-oil microemulsion system (water/n-decane/AOT) showed that the critical dynamics of this three-component microemulsion is completely governed by a Debye cut-off wavenumber qD, which is equal to the inverse diameter of the microemulsion droplet. Furthermore, the authors found occurrence of a crossover phenomenon for the statics and dynamics, at a correlation length xi c such that qD xi c=1, the crossover temperature being at about 10 degrees C below the critical temperature.