Orientational dynamics of liquids confined in nanoporous sol-gel glasses studied by optical kerr effect spectroscopy.

When a liquid is restricted to volumes on a molecular distance scale, its orientational and translational dynamics are perturbed strongly by the confinement. Nanoporous sol-gel glasses are an excellent model system for studying the effects of confinement on the behavior of liquids, and in this Account we review experiments in which ultrafast optical Kerr effect spectroscopy has been used to study the orientational dynamics of liquids confined in these media. We contrast the effects of confinement on the orientational dynamics of weakly wetting, strongly wetting, and networked liquids, and we discuss the influence of factors such as pore size, molecular shape, and surface chemistry.