Orthotetrahedral crystal structures My(TO4)z (T = Si, Ge, P, As, S, Se, Cl, Br, I):: geometrical-topological analysis, quasi-binary representation, and comparison with the AyXz compounds by the method of coordination sequences

Topological analysis of atomic nets in the crystal structures of 284 anhydrous inorganic salts M-y(TO4)(z) (T = Si, Ge, P, As, S, Se, Cl, Br, I) containing isolated orthogroups TO4 was performed by means of the program package TOPOS 3.2. The topological relations were found among the M-y(TO4)(z) salts and 1164 topological types of the binary compounds A(y)X(z) at the two levels: grey isomorphism and partial isotypism. Using the method of coordination sequences nearly a half (47.5%) of the orthostructures in the quasi-binary representation My[T], were found to match 27 frequent topological types of the binary compounds (NaCl, NiAs, FeB, alpha-Al2O3, etc.). The model of cation arrays was shown to sometimes disagree with the model of atomic nets while comparing; the reasons of such disagreements were discussed.