Darstellung und Kristallstruktur des K₂Sb₄S₇ / Preparation and Crystal Structure of K₂Sb₄S₇

In the K 2 S/Sb 2 S 3 -System the compound K 2 Sb 4 S 7 has been prepared and its structure determined. In this structure there are two differently coordinated Sb-atoms: the Sb I -atoms in the vertices of flat SbS 3 -pyramides have the CN 3 to sulfur, the Sb II -atoms are ψ-trigonal-bipyramidal coordinated with one free position in the equatorial plane. These polyhedra are connected to each other by common corners and edges to a three-dimensional net, which has channels parallel the b-axis, in which the K + -ions are located.