Indexed on: 08 Mar '05Published on: 08 Mar '05Published in: Acta crystallographica. Section C, Crystal structure communications
The structure of the new pentanary thiophosphate rubidium silver diniobium tris(disulfide) tetrathiophosphate, Rb(0.38)Ag(0.5)Nb2PS10, is made up of one-dimensional (infinity)1[Nb2PS10-] chains along the  direction. These chains are separated from one another by Ag+ and disordered Rb+ ions. The Nb2PS10- chain is built up from bicapped trigonal prismatic Nb(2)S(12) units which lie about inversion centres and tetrahedral PS4 groups. The Nb2S12 units are linked together to form linear Nb2S9 chains by sharing S-S prism edges. Short [2.898 (1) and 2.908 (1) A] and long [3.724 (1) A] Nb...Nb distances alternate along the chains, and S(2)2- and S2- anionic species co-exist in the structure. The Ag(+) cation lies on an inversion centre and has distorted octahedral coordination described as a [2+4]-bonding interaction.