Structure and stability of inorganic azides

Abstract

An attempt has been made to correlate the explosive sensitivity of some of the inorganic azides with their crystal structure. The refractive indices of these compounds have been determined. Some qualitative experiments have been made on the rate of decomposition of the azides and isoelectronic cyanates, thiocyanates and fulminates. The decomposition of metallic azides depends on the formation of neutral azide radicals. The explosive sensitivity is therefore determined by the degree of electrical neutrality possessed by the azide group in the lattice. The relative magnitude of the ionization potential of the metal compared with the electron affinity of the azide radical determines the extent to which the valence electron is under the influence of the metal. This also determines the unit cell dimensions of the metallic azide. A consideration of the refractive indices and appropriate crystal structure have led to the conclusion that the explosive sensitivity is dependent on the ionization potential of the metal forming the azide.