Structural varieties of polytypes

We present the results of theoretical analysis of structural varieties of compounds for which polytypism is important. As a result, the possibility of isomeric polytype varieties existing has been established, as well as regularities in their formation, depending on the period of repeatability of layers in packaging. In addition, the methods of density functional theory are used to calculate the structure and properties of various polytypic modifications of diamond. Dependences of the interlayer distances and the difference total energy on the hexagonality of diamond polytypes and their isomeric varieties have been found. The theoretical powder X-ray diffraction patterns of diamond polytypes are calculated and their comparative analysis is performed.