SYSTEM NIOBIUM-SULFUR

The following phases have been found in the system niobium-sulfur: NbS3, 2s-NbS2, 3s-NbS2, 2s-Nb1 + xS2, 3s-Nb1 + xS2, Nb3S4, h.t.-Nb1 - xS, l.t.-Nb1 - xS, Nb21S8. While NbS3 is a diamagnetic semiconductor, the other niobium sulfides are metallic with nearly temperature-independent paramagnetism. H.t.-Nb1 - xS, stable above 780 °C, has an orthorhombic structure of the MnP type with infinite zigzag Nb-Nb chains. The low-temperature form of Nb1 - xS has a hexagonal superstructure of the NiAs type with triangular Nb3 clusters. The structures of the other niobium sulfides that had been reported previously, were confirmed. © 1969.