XCN (X = Cl, Br and I): a novel source of isocyanogen

Ambient light photolysis of gaseous BrCN, ClCN, and ICN results in the production of isocyanogen (NCNC) as the sole CN containing product. The flash vacuum pyrolysis of BrCN (1100°C and 10−5 mbar) generates NCNC, NCCN, HOCN, HNCO and the CN radical.