Aluminium fluoride

Chembox new
Name = Aluminum fluoride
ImageFile = Aluminum-trifluoride-3D-polyhedra.png ImageName = Aluminum trifluoride crystal structure
OtherNames = Aluminum(III) fluoride
Aluminum trifluoride
Section1 = Chembox Identifiers
CASNo = 7784-18-1
Section2 = Chembox Properties
Formula = AlF₃
MolarMass = 83.977 g mol⁻¹
Appearance = white, crystalline solid
odorless
Density = 2.91 g cm⁻³, solid
Solubility = insoluble
MeltingPt = 1290 °C
Section7 = Chembox Hazards
EUClass = not listed
NFPA-H = 1
NFPA-F =
NFPA-R =

Aluminum fluoride is the inorganic compound with the formula AlF₃. It can be prepared by treating aluminum hydroxide or aluminum metal with HF. As a solid, its structure resembles that of rhenium trioxide, ReO₃, consisting of distorted AlF₆ octahedra.

AlF₃ is refractory, in strong contrast to the other halides of aluminum. [Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.] AlCl₃, AlBr₃, and AlI₃ are dimeric in the liquid and evaporate as dimers as well. In the gas phase, at ca. 1000 °C, aluminium fluoride exists as trigonal molecules of "D_3h" symmetry group. The Al-F bond lengths are 163 pm.

Aluminium fluoride is an important additive during electrolyte aluminium production because it lowers the melting point of the alumina feed and increases the electrolyte's conductivity.

Aluminium fluoride trihydrate is rarely found in nature as mineral rosenbergite.

References

External Information

[http://loradchemical.com/aluminum-fluoride-4.html Aluminum Fluoride]