Abstract

The arrangement, orientation, and conformation of surfactant molecules at interfaces are of great importance to a wide range of applications. They play a pivotal role in oil recovery, mineral flotation, detergency, coating, and others. Yet despite their importance, still little is known presumably because of limitation of techniques available for their studies. Infrared spectroscopy, for example, suffers from its inability to probe selectively a surface or interface. The recently developed surface- specific sum -frequency generation (SFG) spectroscopy has opened up new opportunity. We report here the results of our application of SFG vibrational spectroscopy to surfactant monolayers adsorbed at various liquid/solid interfaces and show how different interactions can affect the surfactant chain orientation and conformation and hence the properties of an interface.

© 1996 Optical Society of America