Inorganic azides can be classified into (i) ionic salts (e.g., NaN3), (ii) heavymetal azides (e.g., AgN3, PbN3), and (iii) covalently bound nonmetal azides (XN3: X = H, R2B, R3Si, NO, NO2, R2P, halogen; R = alkyl, aryl) (Jones, 1973). Whereas the ionic salts are reasonably stable materials and sodium azide is prepared on a commercial scale, the major use of the heavy-metal azides depends on their explosive nature (Greenwood and Earnshaw, 1984). Particularly, lead azide is used for detonators because of its reliability under a variety of adverse, especially damp conditions (Köhler and Meyer, 1991). Although the covalent azides have been known since the beginning of this century, it is only in recent years that these azides have found use in preparative chemistry and that their structures have been elucidated (Tornieporth-Oetting and Klapötke, 1993a). The characterization and usage of the covalent nonmetal azides have obviously been hampered by their thermodynamic and kinetic instability. HN3 and all of the halogen azides are very hazardous. Especially dangerous are the pure halogen azides in the condensed phase (Dehnicke, 1983). Violent explosions can also occur in the gaseous state upon sudden variations of the pressure (Dehnicke, 1983).
Weitere Kapitel dieses Buchs durch Wischen aufrufen
- Covalent Inorganic Nonmetal Azides
Inis C. Tornieporth-Oetting
Thomas M. Klapötke
- Springer US
- Chapter 3
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