On the Symmetry of OD‐Structures Consisting of Equivalent Layers

Abstract

Abstract After some introductory remarks a survey is given (in part 2) of the basic notions of OD‐theory, including the concept of the OD‐groupoid family. In part 3 a new procedure is presented for the determination of the OD‐groupoid family of an OD‐crystal from general features of its X‐ray diagrams and applied to two examples. This procedure makes use of a complete list of OD‐groupoid families of which Table 3 contains an important part. For the rest of this list, the changes from a similar list which had been published earlier ist given in this table. The mathematical method used to obtain this list is outlined in part 4.