Crystallographic analysis and features of cation coordination in a series of structures of sulfides with Tl+

摘要

A crystallographic analysis of ellisite Tl3AsS3, fangite Tl3AsS4, lorandite TlAsS2, and synthetic Tl3AsS3 shows that the configuration of atomic positions in these structures is determined mostly by the ordering of S2- anions and the large massive Tl+ cations in a single packing. The standard coordination of the As cation is provided only by the strong covalent As-S bonds; the environment of Tl+ cations varies depending on the geometry of their packing with sulfur.