| |||
| Names | |||
|---|---|---|---|
| Other names triazadienyl fluoride | |||
| Identifiers | |||
3D model (JSmol) | |||
| ChemSpider | |||
| |||
| |||
| Properties | |||
| FN3 | |||
| Molar mass | 61.019 g/mol | ||
| Appearance | Yellow-green gas | ||
| Density | 1.3 g/cm3[1] | ||
| Melting point | −139 °C (−218 °F; 134 K)[2] | ||
| Boiling point | −30 °C (−22 °F; 243 K)[2] | ||
| Explosive data | |||
| Shock sensitivity | Extreme | ||
| Friction sensitivity | Extreme | ||
| Hazards | |||
| Occupational safety and health (OHS/OSH): | |||
Main hazards | Extremely sensitive explosive | ||
| NFPA 704 (fire diamond) | |||
| Related compounds | |||
Othercations | Hydrazoic acid Chlorine azide Bromine azide Iodine azide | ||
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |||
Fluorine azide ortriazadienyl fluoride is a yellow green gas composed ofnitrogen andfluorine with formulaFN3.[3] Its properties resemble those ofClN3,BrN3, andIN3.[4] The bond between the fluorine atom and the nitrogen is very weak, leading to this substance being very unstable and prone to explosion.[5] Calculations show the F–N–N angle to be around 102° with a straight line of 3 nitrogen atoms.[6]
It was first made by John F. Haller in 1942.[7]
Fluorine azide can be made by reactinghydrazoic acid orsodium azide, with fluorine gas.[2][8]
Fluorine azide decomposes without explosion at normal temperatures to makedinitrogen difluoride:
At higher temperatures such as 1000 °C fluorine azide breaks up intonitrogen monofluoride radical:[8]
The FN itself dimerizes on cooling.
Solid or liquidFN3 can explode, releasing a large amount of energy. A thin film burns at the rate of 1.6 km/s.[9] Due to the explosion hazard, only very small quantities of this substance should be handled at a time.[10]
FN3adducts can be formed with theLewis acidsboron trifluoride (BF3) andarsenic pentafluoride (AsF5) at -196 °C. These molecules bond with the first nitrogen atom from the fluorine.[11]
| Parameter | Value[10] | Unit |
| A | 48131.448 | MHz |
| B | 5713.266 | MHz |
| C | 5095.276 | MHz |
| μa | 1.1 | |
| μb | 0.7 |
Distances between atoms are F–N 0.1444 nm, FN=NN 0.1253 nm and FNN=N 0.1132 nm.[10]
FN3adsorbs on to solid surfaces ofpotassium fluoride, but not ontolithium fluoride orsodium fluoride. This property was being investigated so thatFN3 could boost the energy of solid propellants.[1]
The ultravioletphotoelectric spectrum shows ionisation peaks at 11.01, 13,72, 15.6, 15.9, 16.67, 18.2, and 19.7 eV. Respectively these are assigned to the orbitals: π, nN or nF, nF, πF, nN or σ, π and σ.[5]
Media related toFluorine azide at Wikimedia Commons
