Trinitrogen also known as the azide radical is an unstable molecule composed of three nitrogen atoms. Two arrangements are known: a linear form with double bonds and charge transfer, and a cyclic form. Both forms are highly unstable, though the linear form is the more stable of the two.[1] 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.[2][3]
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Names | |||
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Other names
Azide radical
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Identifiers | |||
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3D model (JSmol)
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ChEBI |
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ChemSpider |
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770 | |||
PubChem CID
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Properties | |||
N3 | |||
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).
Infobox references
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The linear form of N3 was discovered in 1956 by B. A. Thrush[4] by photolysis of hydrogen azide.[5] 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.[1]
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.[4][1] The ring has C2v symmetry[1]—an isosceles triangle—in contrast to the linear form that has equal N–N bond-lengths.