tribromovanadium

Vanadium(III) bromide, also known as vanadium tribromide, is VBr3. In the solid-state, this species is a polymeric with octahedral vanadium(III) surrounded by six bromide ligands.
VBr3 has been prepared by treatment of VCl4 with HBr:
2 VCl4 + 8 HBr → 2 VBr3 + 8 HCl + Br2
The reaction proceeds via the unstable vanadium(IV) bromide, VBr4, which releases Br2 at room temperature.
Like VCl3, VBr3 forms red-brown soluble complexes with dimethoxyethane and THF, such as mer-VBr3(THF)3.
Aqueous solutions prepared from VBr3 contain the salt trans-[VBr2(H2O)4]+. Evaporation of these solutions give the salt trans-[VBr2(H2O)4]Br.