Séminaire

Mardi 9 Avril 2019 à 11h00.

Modern Alchemy: Liquid Ice and Solid Water

''In this seminar, I will discuss two manifestations of solid—liquid transitions in absence of a phase change. First, I will show how non-linear optical techniques can be used to study the surface structure of ice. By combining a mid-infrared with a near-visible laser beam at a surface, a vibrational spectrum of molecules can be measured with extremely high surface specificity. The vibrational spectrum of the surface of ice is found to strongly resemble that of liquid water at temperatures above –30 ˚C, which implies the presence of a layer of liquid water at the ice surface (in thermal equilibrium!). This liquid-water layer is directly linked to the slipperiness of ice. In the second part of the talk, I will focus on aqueous gels with a yield-stress. I will show how the solid—liquid transition in the rheology of these gels influences the film thickness in coating applications.''