The mixed-metal tris­(di­sulfide) thio­phosphate, KNb(1.77)Ta(0.23)PS(10)

The title compound catena-poly[potassium [tri-μ-disulfido-μ-tetra­thiophos­pha­to-di[niobate(IV)/tantalate(IV)(0.885/0.115)]]], has been obtained through the reaction of the elements with KCl. The title compound is isostructural with KNb(2)PS(10), with the Nb sites occupied by statistically disordered Nb (88.5%) and Ta (11.5%) atoms. The structure is composed of anionic (∞) (1)[M (2)PS(10)](−) chains along [100] (M = Nb/Ta) and K(+) ions. This chain is built up from distorted bicapped trigonal prisms [MS(8)] and [PS(4)] tetra­hedra. There are no inter­chain bonding inter­actions, except for electrostatic and van der Waals forces. The S(2) (2−) and S(2−) anionic species and the M (4+)–M (4+) pair [M—M = 2.8939 (3) Å] are observed. The classical charge balance is represented by [K(+)][M (4+)](2)[PS(4) (3−)][S(2) (2−)](3).