Tungsten hexabromide, also known as tungsten(VI) bromide, is a chemical compound of

tungsten Tungsten (also called wolfram) is a chemical element; it has symbol W and atomic number 74. It is a metal found naturally on Earth almost exclusively in compounds with other elements. It was identified as a distinct element in 1781 and first ...

and

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 ...

with the formula . It is an air-sensitive dark grey powder that decomposes above 200 °C to

tungsten(V) bromide Tungsten(V) bromide is the inorganic compound with the empirical formula W Br5. The compound consists of bioctahedral structure, with two bridging bromide ligands, so its molecular formula is W2Br10. Preparation and structure Tungsten(V) bromide ...

and bromine.

Production and reactions

Tungsten hexabromide is mainly produced by the reaction of metallic tungsten and bromine at temperatures around 100 °C in a nitrogen atmosphere: : Another method of producing this compound is by the reaction of

tungsten hexacarbonyl Tungsten hexacarbonyl (also called tungsten carbonyl) is an organometallic compound with the formula W(CO)6. This complex gave rise to the first example of a dihydrogen complex.Kubas, G. J., Metal Dihydrogen and σ-Bond Complexes, Kluwer Academic ...

and bromine at room temperature, releasing

carbon monoxide Carbon monoxide (chemical formula CO) is a poisonous, flammable gas that is colorless, odorless, tasteless, and slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...

. It can also be produced by the metathesis reaction of

boron tribromide Boron tribromide, BBr3, is a colorless, fuming liquid compound containing boron and bromine. Commercial samples usually are amber to red/brown, due to weak bromine contamination. It is decomposed by water and alcohols. Chemical properties Boron ...

and

tungsten hexachloride Tungsten hexachloride is an inorganic chemical compound of tungsten and chlorine with the chemical formula . This dark violet-blue compound exists as volatile crystals under standard conditions. It is an important starting reagent in the prepar ...

. is reduced with elemental

antimony Antimony is a chemical element; it has chemical symbol, symbol Sb () and atomic number 51. A lustrous grey metal or metalloid, it is found in nature mainly as the sulfide mineral stibnite (). Antimony compounds have been known since ancient t ...

at elevated temperatures, consecutively producing, , , , , then finally at 350 °C. This reaction produces

antimony tribromide Antimony tribromide ( Sb Br3) is a chemical compound containing antimony in its +3 oxidation state. Production Antimony tribromide may be made by the reaction of antimony with elemental bromine, or by the reaction of antimony trioxide with hydrob ...

as a side product. Any of these bromides can be reverted to the hexabromide by oxidation with bromine at 160 °C. Tungsten hexabromide is hydrolyzed in water, producing

tungsten pentoxide Tungsten pentoxide () was reported in early literature but proved to have the stoichiometry W18O49.Wells A.F. (1984) ''Structural Inorganic Chemistry'' 5th edition Oxford Science Publications Sometimes called mineral blue, it is a blue solid for ...

and releasing bromine.

Tungsten(VI) oxytetrabromide Tungsten(VI) oxytetrabromide is the inorganic compound with the formula . This a red-brown, hygroscopic solid sublimes at elevated temperatures. It forms adducts with Lewis bases. The solid consists of weakly associated square pyramidal monomers. ...

is produced by the reaction of tungsten hexabromide and

tungsten(VI) oxide Tungsten(VI) oxide, also known as tungsten trioxide is a chemical compound of oxygen and the transition metal tungsten, with formula WO3. The compound is also called tungstic anhydride, reflecting its relation to tungstic acid . It is a light ...

: :

Structure

The trigonal crystal structure of consists of isolated octahedra and is isostructural with α-.

References

{{Bromides Tungsten halides Bromides