Crystal structure of the mixed-metal thiophosphate Nb1.18V0.82PS10

Abstract

The mixed-metal thiophosphate, Nb1.18V0.82PS10(niobium vanadium phosphorus decasulfide), has been prepared though solid state reactions using an alkali-metal halide flux. The title compound is isostructural with two-dimensional Nb2PS10. [M2S12] (M= Nb or V) dimers built up from two bicapped trigonal prisms and tetrahedral [PS4] units share sulfur atoms to construct1∞[M2PS10] chains along theaaxis. These chains are linked through the disulfide bonds between [PS4] units in adjacent chains to form layers parallel to theabplane. These layers then stack on top of each other to complete the three-dimensional structure with van der Waals gaps. TheMsites are occupied by 59% of Nb and 41% of V and the averageM—S andM—Mdistances in the title compound are in between those of V2PS10and Nb2PS10. The classical charge balance of the title compound can be represented by [(Nb/V)4+]2[P5+][S2−]3[S−]7.