Cation partitioning in ternary vanadium sulfides AV(2)S(4)(A = Ti, Cr, Fe,Ni)

A combination of time-of-flight powder neutron diffraction and powder X-ray diffraction has been used to investigate changes in the cation distributio n in a series of isostructural (space group I2/m a approximate to 5.9, b ap proximate to 3.3 c approximate to 11.3 Angstrom, beta approximate to 92 deg rees) ternary vanadium sulfides, AV(2)S(4) (A = Ti, Cr, Fe, Ni). A progress ive change from an inverse Cr3S4 structure, when A is drawn from the left o f the transition series, to a normal Cr3S4 structure, when A is drawn from the right of the series, occurs. The magnetic susceptibility of all materia ls has a significant temperature-independent component and both spin-glass behaviour [A = Cr, T-g = 15(3) K] and long-range magnetic order [A = Fe,,= 135(3) K] are observed.