Any of a group of compounds having the characteristic formula R(N3)x. R may be almost any metal atom, a hydrogen atom, a halogen atom, the ammonium radical, a complex ([CO(NH3)6], [Hg(CN)2M] with M = Cu, Zn, Co, Ni) an organic radical like methyl, phenyl, nitrophenol, dinitrophenol, p-nitrobenzyl, ethyl nitrate, etc., and a variety of other groups or radicals. The azide group has a chain structure rather than a ring structure. All the heavy metal azides, such as hydrogen azide, and most if not all of the light metal azides (under appropriate conditions) are explosive. They should be handled with utmost care and protected from light, shock, and heat. Many of the organic azides are also explosive.See Lead Azide; Hydrazoic Acid.