Capillary Waves and Bending Elasticity of Monolayers on Water Studied by X-Ray Reflectivity as a Function of Surface Pressure
Résumé
Thermally induced capillary waves on a monolayer of behenic acid on water have been investigated by x-ray reflectivity. The corresponding roughness is measured as a function of the surface pressure. The experimental data are discussed using a theory of thermal fluctuations. A strong decrease in the roughness is observed at the transition to the solid state. This striking feature is attributed to the rigidity of the monolayer in the solid phase whose value has been determined.