Bromine trifluoride is an interhalogen compound with the formula BrF<sub>3</sub>. At room temperature, it is a straw-coloured liquid with a pungent odor
Synthesis
Bromine trifluoride was first described by Paul Lebeau in 1906, who obtained the material by the reaction of bromine with fluorine at 20 °C:
:
The disproportionation of bromine monofluoride also gives bromine trifluoride:
:
Structure
Like ClF<sub>3</sub> and IF<sub>3</sub>, the BrF<sub>3</sub> molecule is T-shaped and planar. In the VSEPR formalism, the bromine center is assigned two electron lone pairs. The distance from the bromine atom to each axial fluorine atom is 1.81 Å and to the equatorial fluorine atom is 1.72 Å. The angle between an axial fluorine atom and the equatorial fluorine atom is slightly smaller than 90° — the 86.2° angle observed is due to the repulsion generated by the electron pairs being greater than that of the Br-F bonds.
Chemical properties
In a highly exothermic reaction, BrF<sub>3</sub> reacts with water to form hydrobromic acid and hydrofluoric acid:
:
BrF<sub>3</sub> is a fluorinating agent, but less reactive than ClF<sub>3</sub>. Already at −196 °C, it reacts with acetonitrile to give 1,1,1-trifluoroethane.
: + Br<sub>2</sub> + N<sub>2</sub>
The liquid is conducting, owing to autoionisation:
:
References
External links
- WebBook page for BrF3
<!-- - replaced this with fluorides (per the suffix (last part) of the name):
------->