ABSTRACT
This chapter describes the techniques used to scatter off the surface of water, and then discusses some recent experiments. It provides a few examples of the kinds of things that X-rays can tell people about Langmuir monolayers. The simplest X-ray scattering technique used to study surfaces is specular reflectivity. A simplified picture of reflection from a monolayer on a substrate is that X-rays are reflected both from the monolayer-air interface and the monolayer-substrate interface; interference between these two reflections gives rise to intensity maxima. Determining the symmetries of various phases is one of the very simplest things that can be done with X-ray diffraction. In any case X-ray diffraction is one of the core characterization tools for anyone working with three-dimensional materials, and there is no reason why it should not be so for monolayers as well.
