Title: Niobium Pentafluoride
CAS Registry Number: 7783-68-8
Additional Names: Columbium pentafluoride
Molecular Formula: F5Nb
Molecular Weight: 187.90
Percent Composition: F 50.55%, Nb 49.44%
Line Formula: NbF5
Literature References: Prepn from NbCl5 + HF: Ruff, Zedner, Ber. 42, 492 (1909); Ruff, Schiller, Z. Anorg. Allg. Chem. 72, 329 (1911); Kwasnik in Handbook of Preparative Inorganic Chemistry Vol. 1, G. Brauer, Ed. (Academic Press, New York, 2nd ed., 1963) p 254. Prepn from the elements: Fairbrother, Frith, J. Chem. Soc. 1951, 3051; Junkins et al., J. Am. Chem. Soc. 74, 3464 (1952). Review of transition metal pentafluorides: Peacock, Adv. Fluorine Chem. 7, 113-145 (1973).
Properties: Strongly refractive, deliquescent, monoclinic crystals, d480 2.6955. mp 80.0°; bp 234.9°. Appreciable vapor pressure at 50°. Hydrolyzes in water, alc, caustic solns. Sparingly sol in carbon disulfide, chloroform. More sol in concd H2SO4 than TaF5. Forms complexes with Lewis bases.
Melting point: mp 80.0°
Boiling point: bp 234.9°
Density: d480 2.6955 |