Nitryl azide (tetranitrogen dioxide) is an inorganic compound with the chemical formula . It is an unstable nitrogen oxide consisting of a covalent nitrogenâÂÂnitrogen bond between a nitro group and an azide group. It has been detected by infrared spectroscopy as a short-lived product of the reaction between sodium azide and nitronium hexafluoroantimonate:
It is also the product of nitryl chloride and silver azide.
The compound quickly decomposes to form two nitrous oxide molecules. Calculations suggest that this process occurs via an oxatetrazole oxide intermediate: