Niobium(IV) fluoride

Unit cell of niobium(IV) fluoride.
Names
IUPAC name Niobium(IV) fluoride
Other names Niobium tetrafluoride
Identifiers
CAS Number	13842-88-1 Y
3D model (JSmol)	Interactive image
ChemSpider	9253762
PubChem CID	11078613
InChI InChI=1S/4FH.Nb/h4*1H;/q;;;;+4/p-4 Key: TUDPVASEPFIHNB-UHFFFAOYSA-J
SMILES F[Nb](F)(F)F
Properties
Chemical formula	NbF4
Molar mass	168.9 g/mol
Appearance	black solid
Melting point	350 °C (662 °F; 623 K) (decomposes)
Structure[1]
Crystal structure	tetragonal
Point group	I4/mmm
Lattice constant	a = 4,0876(5) Å, c = 8,1351(19) Å
Coordination geometry	[6]Nb
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Niobium(IV) fluoride is a chemical compound with the formula NbF₄. It is a nonvolatile black solid.

Properties

NbF₄ absorbs vapor strongly and turns into NbO₂F in moist air. It 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:^[2]

2 NbF₄ → NbF₅ + NbF₃ (at 350 °C)

Structure

Niobium(IV) fluoride adopts a crystal structure analogous to that of tin(IV) fluoride, in which each niobium atom is surrounded by six fluorine atoms forming an octahedron. Of the six fluorine atoms surrounding a single niobium atom, four are bridging to adjacent octahedra, leading to a structure of octahedra connected in layers.^[1]