Particle statistics in X-ray diffractometry

Abstract

Only those crystallites having the reflecting planes almost parallel to the specimen surface can contribute to a certain reflection. The intensity of the resulting diffraction is thus dependent on this number of crystallites. Intensities of different diffraction lines or between different specimens can only be compared if the number of particles contributing is the same fraction of the total number of particles. If this total number is too small to warrant a random distribution, an error in the intensity measurement is introduced⁸). This may occur for instance when the particles are too large.