A new thiophosphate, Rb0.38Ag0.5Nb2PS10

The structure of the new pentanary thio­phosphate rubidium silver diniobium tris(disulfide) tetrathio­phosphate, Rb0.38Ag0.5Nb2PS10, is made up of one-dimensional {}_{\infty}^{\kern 4pt 1}[Nb2PS{}_{10}^{\,- }] chains along the [001] direction. These chains are separated from one another by Ag+ and disordered Rb+ ions. The Nb2PS{}_{10}^{\,- } chain is built up from bicapped trigonal prismatic Nb2S12 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) Å] and long [3.724 (1) Å] 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.