The coordination polyhedra ZnSn in crystal structures

Voronoi-Dirichlet polyhedra (VDP) and the intersecting sphere method were used to analyze the coordination of zinc atoms in the structures of all known compounds containing ZnSn polyhedra. The Zn(II) atoms were found to coordinate 6, 5, 4, 3, or 2 sulfur atoms to form coordination octahedra or trigonal prisms (n = 6), trigonal bipyramids (n = 5), tetrahedra (n = 4), triangles ZnS3, or dumbbells ZnS2. The effect of the coordination number of zinc atoms on the key parameters of zinc VDP is considered. A common linear dependence of the solid angles of the VDP faces corresponding to both valence and non-valence Zn-S contacts on the interatomic distances was established to exist. Although the Zn-S bond lengths vary over a broad range (2.39 to 3.29 Å), the Zn VDP volume almost does not depend on its C.N. with respect to sulfur. Some characteristic features of Zn stereochemistry are considered from the 18-electron rule standpoint.