We studied the water density profile close to spherical and planar hydrophobic objects using molecular dynamics (MD) simulations. For normal pressure and room temperature, the depletion layer thickness of a planar substrate is approximately 2.5 Angstroms. Even for quite large spherical solutes with a radius of R = 18 Angstroms, the depletion layer thickness is reduced by 30%, which shows that substrate curvature and roughness is an experimentally important factor. Rising temperature leads to a substantial increase of the depletion layer thickness. The compressibility of the depletion layer is found to be surprisingly small and only approximately 5 times higher than that of bulk water. A high electrostatic surface potential of 0.5 V is found, which presumably plays an important role in the presence of charged solutes, since it can promote adsorption into the interfacial layer.

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The mechanism of a superion phase transition is studied by electro-physical and acoustical methods in lithium iodate of hexagonal modification. The role of structural factors in the mechanism of a phase transition is revealed and the contribution of a correlated motion of the disordered ions to the dielectric parameters is established.Mittels elektrophysikalischer und akustischer Methoden wird der Mechanismus eincs Superion-Phasenubergangs in Lithiumjodat hexagonaler Modifikation untersucht. Die Rolle des Strukturfaktors im Mechanismus des Phasenubergangs wird aufgezeigt und der Beitrag einer korrelierten Bewegung der fehlgeordneten Ionen zu den dielektrischen Parametern festgestellt.