Use of an ellipsoid model for the determination of average crystallite shape and size in polycrystalline samples

摘要

A mathematical model for interpreting the anisotropical broadening of the powder diffraction olines by an average crystallite in the form of a triaxial ellipsoid is developed. The model covers satisfactorily a broad range of averaged crystallite shapes in polycrystalline samples of all crystal symmetries and provides simple formulas for use in powder pattern fitting routines.