Application of the X-ray divergent-beam technique for the determination of the angles between crystal blocks. I. Reflexion from the planes parallel to the crystal surface

A detailed analysis of divergent-beam (DB) X-ray reflexion from a crystal surface is given. It has been shown theoretically and experimentally that DB methods of determining the substructure misorientation described previously yield erroneous results. The paper deals with two rather simple methods of determining the angles between the same planes in neighbouring blocks in the case of reflecting planes being parallel to the crystal surface.