Ambient light photolysis of gaseous BrCN, ClCN, and ICN results in the
production of isocyanogen (NCNC) as the sole CN containing product. T
he flash vacuum pyrolysis of BrCN (1100 degrees C and 10(-5) mbar) gen
erates NCNC, NCCN, HOCN, HNCO and the CN radical.