Sum-frequency vibrational spectroscopy of the solid/liquid interface

Sum-frequency spectroscopy (SFS) is a non-linear optical technique that yields vibrational spectra of molecules at interfaces. A brief summary of the theoretical background to SFS is provided and the origin of its unusual selection rules is explained. The application of SFS to the study of organic molecules at the solid/liquid interface is reviewed. Areas covered include liquid structure at solid surfaces, electrochemistry and the adsorption of surfactants at the solid/water interface.