Document Type
Article
Publication Date
9-2014
Abstract
Forced Rayleigh scattering is used to study the tracer diffusion of an azobenzene in binary combinations of polar solvents, including water. In the absence of water, the tracer diffusion coefficient D in the mixture lies between the diffusion coefficients within the pure solvents, on a curve that is reasonably close to the prediction of free-volume theory. If water is present, on the other hand, the diffusion coefficient displays a minimum that is less than the smaller of the two pure-solvent values. We attempt to understand the different behavior in water by concentrating on the fairly hydrophobic nature of the solute, leading to a first solvent shell that is hydrophobic on the inside and hydrophilic on the outside. We also believe that clusters of amphiphiles explain the observation that, in aqueous combinations, D is nearly constant above a certain amphiphile mole fraction.
Identifier
10.1063/1.4896303
Publisher
American Institute of Physics
Repository Citation
Frasch, D.M., & Spiegel, D.R. (2014). Experiments on tracer diffusion in aqueous and non-aqueous solvent combinations. Journal of Chemical Physics, 141(12), 124507. doi: 10.1063/1.4896303
Publication Information
The Journal of Chemical Physics