Indexing of Powder Diffraction Patterns

Abstract

AbstractDespite the advances of the electron mtcrodiflraction technique, the determination of unit cells of microcrystalline compounds still depends in many cases on the interpretation of the X-ray powder pattern. The feasibility of this interpretation depends strongly un the precision of the data, the present-day level of which is far from its physical limit. It could be improved by application of monochromators in diflractometry. Some possible methods are discussed. With regard to interpretation, a survey of existing methods is given (Lipson, Ito, de Wolff, Szoldos). Some of these techniques are suitable for computers, at least in the initial phase of the procedure. This is illustrated by application of a zone-finding program for the complete solution of a given pattern. Finally, the influence of impurities and other disturbing factors is discussed.