Thermodynamic description of dielectric relaxation in interfacial liquid

The study proposes thermodynamic approach to describe dielectric relaxation in interfacial layers of polar liquids. It explicitly accounts for contribution of interfacial energies to Helmholtz potential and to relaxation energy barrier formation. An analytical expression is derived that relates activation energy and relaxation time to layer thickness and change in interfacial free energy. Experimental spectra of adsorbed water show exponential increase in relaxation time with decreasing layer thickness, confirming localized influence of solid–liquid interface and supporting thermodynamic model of dielectric relaxation. The results demonstrate the applicability of this thermodynamic description to thin interfacial liquid layers.