Niobium(V) fluoride

Niobium(V) fluoride
IUPAC name Niobium(V) fluoride Niobium pentafluoride
Identifiers
CAS number	7783-68-8 Y
PubChem	82217
Properties
Molecular formula	NbF5
Molar mass	187.898 g/mol
Appearance	colorless monoclinic crystals hygroscopic
Density	3.293 g/cm3
Melting point	72-73 °C
Boiling point	236 °C
Solubility in water	reacts
Solubility	slightly soluble in chloroform, carbon disulfide, sulfuric acid
Hazards
EU Index	Not listed
Flash point	Non-flammable
Related compounds
Other anions	Niobium(V) chloride Niobium(V) bromide Niobium(V) iodide
Other cations	Vanadium(V) fluoride Tantalum(V) fluoride
Related niobium fluorides	Niobium(III) fluoride Niobium(IV) fluoride
Y fluoride (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Niobium(V) fluoride, also known as niobium pentafluoride, is a colorless crystalline solid often used as a starting material in niobium chemistry.

Preparation

Niobium pentafluoride is obtained as an intermediate during the recovery of niobium metal from its ores. It also can be prepared by direct fluorination of niobium metal at 250 to 300°C, either by fluorine gas or anhydrous hydrofluoric acid. The pentafluoride vapors are condensed in a pyrex or quartz tube from which it is sublimed at 120°C under vacuum and collected as colorless crystals.

Also, niobium pentafluroide can be prepared by the reaction of fluorine with niobium pentachloride:

2NbCl₅ + 5F₂ → 2NbF₅ + 5Cl₂

External links

• NIST Standard Reference Database