Nitrogen monofluoride (fluoroimidogen) is a metastable species that has been observed in laser studies. It is isoelectronic with O
2. Like
boron monofluoride, it has unusual higher than single-bonded fluorine. It is unstable with respect to its formal dimer,
dinitrogen difluoride, as well as to its elements,
nitrogen and
fluorine. Nitrogen monofluoride can be formed by the decomposition of
fluorine azide into N
2F
2 and N
2. It is also produced when various
radical species (H, O, N, CH
3) react with
nitrogen difluoride (NF
2) to abstract one fluorine atom. Many of the reactions give the product in an
excited state that has a characteristic
chemiluminescence, and have thus been investigated for development as a
chemical laser. The reactions are highly efficient and the product has a long lifetime. The reaction with molecular hydrogen (H
2) involves a
chain propagation via regeneration of the atomic hydrogen radical that can perpetuate for many cycles. An alternative azide process involves the reactino of atomic fluorine with
hydrazoic acid to give an azide radical, which then reacts with another atomic fluorine to produce NF with N
2 as a byproduct. This route avoids the necessity of using atomic hydrogen, a chemical that could otherwise cause the decomposition of NF.