3D model (JSmol)
|Molar mass||42.021 g·mol−1|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Trinitrogen also known as the azide radical is an unstable molecule composed of three nitrogen atoms. Two arrangements are possible: a linear form with double bonds and charge transfer, and a cyclic form. Both forms are highly unstable. More-stable derivatives exist, such as when it acts as a ligand, and it may participate in azido nitration, which is a reaction between sodium azide and ammonium cerium nitrate.
The linear form of N3 was discovered in 1956 by B. A. Thrush by photolysis of hydrogen azide. As a linear and symmetric molecule, it has D∞h symmetry, with a nitrogen–nitrogen bond length averaging 1.8115 Å. The first excited electronic state, A2Σu, is 4.56 eV above the ground state.
The cyclic form was identified in 2003 by N. Hansen and A. M. Wodtke using ultraviolet photolysis of chlorine azide. Although the reaction yielded mostly the linear form, about 20% of the molecules were cyclic.
- Schlegel, H. Bernhard; Skancke, Anne (August 1993). "Thermochemistry, energy comparisons, and conformational analysis of hydrazine, triazane, and triaminoammonia". Journal of the American Chemical Society. 115 (16): 7465–7471. doi:10.1021/ja00069a053.
- Kuchitsu, K, ed. (1998). Inorganic Molecules. Landolt-Börnstein - Group II Molecules and Radicals. Vol. 25A. doi:10.1007/b59072. ISBN 3-540-61713-2.
- Jin, Lin; Yu, Xue-fang; Pang, Jing-lin; Zhang, Shao-wen; Ding, Yi-hong (30 July 2009). "Theoretical Study on the Reactions of the Cyclic Trinitrogen Radical toward Oxygen and Water". The Journal of Physical Chemistry A. 113 (30): 8500–8505. Bibcode:2009JPCA..113.8500J. doi:10.1021/jp810741v. PMID 19719307.
- Thrush, B. A. (10 April 1956). "The Detection of Free Radicals in the High Intensity Photolysis of Hydrogen Azide". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 235 (1200): 143–147. Bibcode:1956RSPSA.235..143T. doi:10.1098/rspa.1956.0071. S2CID 95714517.
- Hansen, N.; Wodtke, A. M. (December 2003). "Velocity Map Ion Imaging of Chlorine Azide Photolysis: Evidence for Photolytic Production of Cyclic-N3". The Journal of Physical Chemistry A. 107 (49): 10608–10614. Bibcode:2003JPCA..10710608H. doi:10.1021/jp0303319.
- Media related to Trinitrogen at Wikimedia Commons