X‐ray Diffraction Techniques for Soil Mineral Identification

This chapter is devoted to X-ray powder diffraction (XRD), since that is the technique most applicable to soil mineralogy. Obtaining useful information from XRD requires the ability to control and/or measure angular relations between incident and diffracted radiation. Two types of instruments have been used to perform X-ray powder diffraction analysis: the XRD powder camera and the X-ray diffractometer. Modern diffractometers have anumber of advantages over the powder camera and are the more commonly used instruments in soil mineralogy. Therefore, the chapter emphasizes the diffractometer approach. Sample preparation is an important aspect of soil mineralogical analysis by XRD. The chapter provides explanations and detailed procedures pertaining to sample preparation. One fundamental consideration is that diffraction is only detected for the atomic crystal planes that are coplanar with the focal plane of the diffractometer.