dark gray; fcc, a=0.4388nm; hardness, 8+ Mohs; electrical resistivity 78μοhm· cm; transition temp 15.2K; can be prepared by heating Nb metal in excess N2 or NH3 to 700°C–1100°C; used in the form of 99.5% pure sputtering target for increasing electrical stability of diodes, transistors, and integrated circuits [KIR81] [CIC73] [CER91]
Dark gray crystals. Transition
temperature 15.2 K. Insoluble in
HCL, HNO3 and H2SO4; but attacked by hot caustic, lime, or
strong alkalis evolving NH3.
Niobium nitride is used as superconductor. Used in absorbing?anti-reflective coatings. It used to produce arc-welding rods and in steel.
Niobium nitride (NbN) thin films were noticed at an early stage because of their critical transition temperatures as low as 16-17K which could find wide applications in superconducting microelectronics. Because of its complicated phase diagram, NbN is difficult to prepare in the pure face-centered cubic, rocksalt structure.
