Molecular structure and dynamics of water at the water-air interface studied with surface-specific vibrational spectroscopy

Angew Chem Int Ed Engl. 2015 May 4;54(19):5560-76. doi: 10.1002/anie.201411188. Epub 2015 Apr 15.

Abstract

Water interfaces provide the platform for many important biological, chemical, and physical processes. The water-air interface is the most common and simple aqueous interface and serves as a model system for water at a hydrophobic surface. Unveiling the microscopic (<1 nm) structure and dynamics of interfacial water at the water-vapor interface is essential for understanding the processes occurring on the water surface. At the water interface the network of very strong intermolecular interactions, hydrogen-bonds, is interrupted and the density of water is reduced. A central question regarding water at interfaces is the extent to which the structure and dynamics of water molecules are influenced by the interruption of the hydrogen-bonded network and thus differ from those of bulk water. Herein, we discuss recent advances in the study of interfacial water at the water-air interface using laser-based surface-specific vibrational spectroscopy.

Keywords: aqueous interface; molecular dynamics; sum-frequency spectroscopy; time-resolved spectroscopy; water-air interface.