Background

A crystallite is the smallest unit contributing to X-ray diffraction and is defined as a domain that is treated as a single crystal in crystalline grains. It is known that the chemical and physical properties of industrial products correlate with the crystallite size, so it is very important to accurately measure the crystallite size. The Scherrer method, the Williamson-Hall method, and the FP (fundamental parameter) method are used to determine crystallite size from X-ray diffraction profiles. In particular, the FP method allows the precise calculation of crystallite size and distribution because it can correct the width of the diffraction peak using information about the optical system used on the diffractometer. In this example, we verified the validity of the values by comparing the crystallite size calculated with the FP method to the results measured using other methods.