Cyanogen

Cyanogen is a chemical compound C₂N₂. The CN entity behaves like a halogen. As do halogens, it forms molecules consisting of two CN groups, C≡N-N≡C. Compounds containg the CN group are called cyanides, cyanates, and isocyanates. "Cyanogen" refers to a single CN group in some molecules, such as cyanogen chloride (NCCl).