Rhenium(III) bromide is a chemical compound with the formula Re₃Br₉. It is a black lustrous crystalline solid. This compound reacts with water to form

rhenium(IV) oxide Rhenium(IV) oxide or rhenium dioxide is the inorganic compound with the formula ReO2. This gray to black crystalline solid is a laboratory reagent that can be used as a catalyst. It adopts the rutile structure. Synthesis and reactions It forms v ...

and is isostructural with rhenium(III) chloride.

Preparation

This compound is prepared by the reaction of

rhenium Rhenium is a chemical element; it has symbol Re and atomic number 75. It is a silvery-gray, heavy, third-row transition metal in group 7 of the periodic table. With an estimated average concentration of 1 part per billion (ppb), rhenium is one ...

metal 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 ...

gas at 500 °C under

nitrogen Nitrogen is a chemical element; it has Symbol (chemistry), symbol N and atomic number 7. Nitrogen is a Nonmetal (chemistry), nonmetal and the lightest member of pnictogen, group 15 of the periodic table, often called the Pnictogen, pnictogens. ...

: :6Re + 9Br₂ → 2Re₃Br₉ If there is oxygen in the atmosphere, it will instead form rhenium(III) oxybromide. However, the most common method of producing this compound is by first reacting

potassium hexabromorhenate(IV) Potassium hexabromorhenate is an inorganic chemical compound with the chemical formula . Synthesis Fusion of rhenium with potassium bromide in a bromine vapor current: :: The effect of hydrobromic acid on a mixture of potassium bromide with rhen ...

with

silver nitrate Silver nitrate is an inorganic compound with chemical formula . It is a versatile precursor to many other silver compounds, such as those used in photography. It is far less sensitive to light than the halides. It was once called ''lunar causti ...

, which forms silver hexabromorhenite(IV), then this compound is heated to 600 °C to form rhenium(III) bromide. :K₂ReBr₆ + 2AgNO₃ → Ag₂ReBr₆ + 2KNO₃ :6Ag₂ReBr₆ → 12AgBr + 3Br₂ + 2Re₃Br₉ An alternative method is a thermal decomposition of rhenium(V) bromide.

References

{{Bromides Rhenium compounds Bromides