Niobium(IV) fluoride

Niobium(IV) fluoride

Names
IUPAC name Niobium(IV) fluoride
Identifiers
CAS Number	13842-88-1
Properties
Chemical formula	NbF4
Molar mass	168.9 g/mol
Appearance	black solid
Melting point	350 °C (662 °F; 623 K) (decomposes)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
verify (what is  ?)
Infobox references

Niobium(IV) fluoride is a chemical compound with the formula NbF₄; it is a nonvolatile black solid. It absorbs vapor strongly. It turns into NbO₂F in moist air. NbF₄ reacts with water to form a brown solution and a brown precipitate whose components are unknown. It is stable between 275 °C and 325 °C when heated in a vacuum. However, it disproportionates at 350 °C rapidly to form niobium(V) fluoride and niobium(III) fluoride:

$\mathrm{\ 2 NbF_4 \rightarrow NbF_5 + NbF_3}$(at 350 °C)^[1]

References

1. 张青莲 (1981). 无机化学丛书. Beijing: Science Press. p. 323. ISBN 7-03-002238-6.