Nitrogen triiodide (Molecule of the Month for March 2007)
Nitrogen triiodide is a sensitive contact explosive, small quantities explode with a gunpowder-like snap when touched even lightly or even blowing on it, releasing a purple cloud of iodine vapor and nitrogen gas.
The material that is usually called "nitrogen triiodide" is prepared by the reaction of iodine with ammonia. When this reaction is conducted at low temperatures in anhydrous ammonia, the initial product is NI3·(NH3)5, but this material loses some ammonia upon warming to give the 1:1 adduct NI3·(NH3). Its solid state structure consists of chains of -NI2-I-NI2-I-NI2-I-... Ammonia molecules are situated between the chains. In the dark and kept cold and damp with ammonia, NI3·(NH3) is stable. The dry material is, however a contact explosive decomposing with huge force.
Formal Chemical Name (IUPAC)
Update by Karl Harrison
(Molecule of the Month for March 2007 )