Zirconium(IV) bromide

Zirconium(IV) bromide is the inorganic compound with the formula ZrBr₄. This colourless solid is the principal precursor to other Zr–Br compounds.

Zirconium(IV) bromide

Names
Other names zirconium tetrabromide
Identifiers
CAS Number	13777-25-8 N
3D model (JSmol)	Interactive image
ChemSpider	75549 Y
ECHA InfoCard	100.034.002
EC Number	237-417-4
PubChem CID	83727
CompTox Dashboard (EPA)	DTXSID6065630
InChI InChI=1S/4BrH.Zr/h4*1H;/q;;;;+4/p-4 Y Key: LSWWNKUULMMMIL-UHFFFAOYSA-J Y InChI=1/4BrH.Zr/h4*1H;/q;;;;+4/p-4 Key: LSWWNKUULMMMIL-XBHQNQODAM
SMILES Br[Zr](Br)(Br)Br
Properties
Chemical formula	ZrBr4
Molar mass	410.86 g/mol
Appearance	off-white powder
Density	4.201 g/cm3, solid
Melting point	450 °C (842 °F; 723 K)
Boiling point	sublimes
Solubility in water	reacts with water
Structure
Crystal structure	Cubic, cP40
Space group	P-43m, No. 205
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H314
Precautionary statements	P260, P264, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P363, P405, P501
NFPA 704 (fire diamond)	3 0 2
Related compounds
Other anions	Zirconium(IV) fluoride Zirconium(IV) chloride Zirconium(IV) iodide
Other cations	Titanium tetrabromide Hafnium tetrabromide
Related compounds	Zirconium(III) bromide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Preparation and properties

ZrBr₄ is prepared by the action of bromine on zirconium oxide via a carbothermic reaction:^[1]

ZrO₂ + 2 C + 2 Br₂ → ZrBr₄ + 2 CO

Like many related tetrahalides, it is purified by sublimation.

It can also be prepared by treatment of the borohydride complex with hydrogen bromide:^[2]

Zr(BH₄)₄ + 4 HBr → ZrBr₄ + 4 H₂ + 2 B₂H₆

Like related tetrabromides of Ti and Hf, ZrBr₄ hydrolyzes readily to give the oxybromide, with release of hydrogen bromide.

Structure

No single crystal X-ray study of ZrBr₄ has been described. Some reports suggest that it is isostructural with TiCl₄ and TiBr₄, featuring tetrahedral metal centers.^[3] Other studies indicate a polymeric structure.^[4] ZrCl₄ is polymeric in the solid state, featuring octahedral Zr centers.^[5]