Cation and anion sublattices in a series of typical cristal structures

Abstract: The crystallographic analysis of Rb ₂NaAlF ₆(Fd(Formula presented.)m) and (Al,V) ₄(P ₄O ₁₂) ₃((Formula presented.)3d) cubic structures and the trigonal structure of phenakite Be ₂SiO4 R(Formula presented.) is performed. In Rb ₂NaAlF ₆ a large and heavy Rb cation stabilizes cation and anion sublattices, promoting their maximum symmetry. In the structure of cyclic tetraphosphate, the core is formed by the cation sublattice with a noticeable deviation of P cations from its nodes. The anion arrangement ordered by pseudo-cubic and hexagonal sublattices with pseudo-symmetry features dominates in the trigonal structure of phenakite.