Selenium tetrabromide is an inorganic compound with a chemical formula SeBr4.

Selenium tetrabromide could be produced by mixing elemental bromine and selenium:[2][3] Selenium tetrabromide exists in two polymorphs, the trigonal, black α-SeBr4 and the monoclinic, orange-reddish β-SeBr4, both of which feature tetrameric cubane-like Se4Br16 units but differ in how they are arranged.

[1] It dissolves in carbon disulfide, chloroform and ethyl bromide, but decomposes in water,[4] so that it produces selenous acid in wet air.

The compound is only stable under a bromine-saturated atmosphere; gas phase measurements of the gas density indicate that the compound decomposes into selenium monobromide and bromine.

[3]