Development of a laboratory EXAFS facility.

The EXAFS technique is a powerful new structural tool, particularly useful for studies of disordered or otherwise complex materials for which x-ray diffraction techniques are difficult or unfeasible. At the present time, most EXAFS experiments are carried out at a synchrotron facility because of the larger fluxes available. We have developed an in-laboratory apparatus utilizing a focusing crystal technique which increases available fluxes two to three orders of magnitude over previous laboratory facilities, so that EXAFS measurements can be carried out quickly and accurately in the laboratory. We will discuss the principles of the focusing monochromator and we will also illustrate the experimental method with examples, including studies of chemical solutions, defect crystalline solids, and high-temperature superconductors.