Peculiarities of Crystal Structure of the Cubic System Compounds with T4 and T5 Space Groups

Resumo

We study symmetry peculiarities of crystalline compounds of a cubic system with the space groups T⁴ and T⁵ caused by the absence of point Wyckoff-sets in the unit cells of these groups. Due to the high multiplicity of the available Wyckoff positions, such compounds possess unit cells of complex composition. In these compounds, pseudosymmetry is realized with high probability when some group of atoms is located in positions close to the positions of higher-symmetry groups. We provide examples of crystalline compounds showing predicted specific structural features.