From abstract: "The preparation of pure molybdenum(IV) bromide was accomplished conveniently by the reaction between molybdenum(III) bromide and liquid bromine at ca. 55°. Molybdenum(IV) bromide was found to be soluble in liquid bromine, and this property was utilized to separate and purify the molybdenum(IV) bromide. The solution of MoBr4 in bromine was a poor electrical conductor. No evidence was found for the formation of MoBr4 from MoBr3 and bromine vapor at 2-4 atm. and temperatures from 180 to 400°. However, MoBr4 was completely decomposed at 110-130°, in vacuo, with formation of MoBr3 and bromine."