Zirconium(IV) bromide is the
inorganic compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''.
Inorgan ...
with the formula ZrBr
4. This colourless solid is the principal precursor to other Zr–Br compounds.
Preparation and properties
ZrBr
4 is prepared by the action of
bromine
Bromine is a chemical element; it has chemical symbol, symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between th ...
on
zirconium oxide
Zirconium dioxide (), sometimes known as zirconia (not to be confused with zirconium silicate or zircon), is a white crystalline oxide of zirconium. Its most naturally occurring form, with a monoclinic crystalline structure, is the mineral badde ...
via a
carbothermic reaction
Carbothermic reactions involve the reduction of substances, often metal oxides (O2-), using carbon (C) as the reducing agent. The reduction is usually conducted in the electric arc furnace or reverberatory furnace, depending on the metal ore. The ...
:
: ZrO
2 + 2C + 2Br
2 → ZrBr
4 + 2CO
Like many related tetrahalides, it is purified by
sublimation.
It can also be prepared by treatment of the borohydride complex with
hydrogen bromide
Hydrogen bromide is the inorganic compound with the formula . It is a hydrogen halide consisting of hydrogen and bromine. A colorless gas, it dissolves in water, forming hydrobromic acid, which is saturated at 68.85% HBr by weight at room temper ...
:
: Zr(BH
4)
4 + 4HBr → ZrBr
4 + 4H
2 + 2B
2H
6
Like related tetrabromides of
Ti and Hf, ZrBr
4 hydrolyzes readily to give the
oxybromide, with release of
hydrogen bromide
Hydrogen bromide is the inorganic compound with the formula . It is a hydrogen halide consisting of hydrogen and bromine. A colorless gas, it dissolves in water, forming hydrobromic acid, which is saturated at 68.85% HBr by weight at room temper ...
.
Structure
No single crystal X-ray study of ZrBr
4 has been described. Some reports suggest that it is isostructural with
TiCl4 and
TiBr4, featuring tetrahedral metal centers. Other studies indicate a polymeric structure. ZrCl
4 is polymeric in the solid state, featuring octahedral Zr centers.
References
{{Bromides
Bromides
Zirconium(IV) compounds
Metal halides