Zirconium(IV) bromide is the
inorganic compound 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 with the symbol Br and atomic number 35. It is the third-lightest element in group 17 of the periodic table ( halogens) and is a volatile red-brown liquid at room temperature that evaporates readily to form a simi ...
on
zirconium oxide
Zirconium dioxide (), sometimes known as zirconia (not to be confused with zircon), is a white crystalline oxide of zirconium. Its most naturally occurring form, with a monoclinic crystalline structure, is the mineral baddeleyite. A dopant stabi ...
via a
carbothermic reaction:
: 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 tempe ...
:
: 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
oxy-bromide, 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 tempe ...
.
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
Zirconium(IV) compounds
Metal halides
{{inorganic-compound-stub