The surface roughness of water/glycerol mixtures investigated by X-ray reflectivity

We report on in situ X-ray reflectivity measurements of the surface roughness of binary mixtures of water and glycerol in a temperature regime from 295 to 210 K. The experimentally determined surface roughness has been found to follow the capillary wave model of simple liquids in the whole temperature region. No influence of the viscosity on the rms roughness has been found and no layer formation has been observed.