Metal hexaammine as a bulky cation : Structural and property studies of [M(NH3)6]Cu8Sb3S13 (M = Mn, Fe, Ni) and [Fe(NH3)6]AgES4 (E = As, Sb)

Five new compounds, which bring together two classical groups, Werner transition-metal hexaammine complexes and sulfosalts, have been prepared from supercritical ammonia. They form in two different structure types which are built from traditional octahedrally coordinated transition-metal hexaammine cations and anionic networks that can be described as metalated derivatives of sulfosalts. The anionic framework of compound I, [Fe(NH3)6]Cu8Sb3S13, is built around a central Cu8S13 core in which copper atoms are surrounded by sulfur atoms in a very distorted tetrahedral coordination. These copper sulfide cores are linked together through bridging antimony atoms which assume a very regular tetrahedral coordination of sulfur atoms. The three mutually orthogonal channels created by the anion are filled with Fe(NH3)6 cations. In [Fe(NH3)6]AgES4 (E = Sb or As), II and III, respectively, the anionic framework is a one-dimensional chain built from alternating E− and Ag−sulfide tetrahedra that share opposite edges. In...