X-ray absorption fine structure for single crystals

Abstract

X-ray absorption fine structure measurements are a prime tool at synchrotrons around the world, accounting for over 30% of all synchrotron research. They are incisive tools for elucidating local structure, ionization state and coordination geometry. However, in general, it has not been possible to apply them to perfect or near-perfect crystals, and their dominant application is to micro-samples, powders, metals and solutions. The reasons for this are given, and an experimental technique to yield high-precision data for good crystals is developed. This widens the applicability of the technique dramatically, and permits standards and calibration samples to be used and transferred for new types of measurement. It is shown that this is particularly appropriate for discrete measurements of absorption, X-ray absorption fine structure and X-ray absorption near-edge spectroscopy, and in cases of strong oscillations.