The isothermal flash photolysis of hydrazoic acid

✍ Scribed by Richard J. Paur; Edward J. Bair

• Publisher: John Wiley and Sons
• Year: 1976
• Tongue: English
• Weight: 702 KB
• Volume: 8
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.550080115

✦ Synopsis

The flash photolysis of HNs was studied by coordinated time-resolved spectroscopic measurements of HN3, NH(u'A), NH(X3z), NH(c'a), NH(A3r), NH2, and N3 following flash photolysis of mixtures of HN3 with argon or helium. The primary photolysis is complex, but when the wavelength distribution of the flash is limited to values greater than about 200 nm, the major reactive product is NH('A), or states which quickly decay to NH('A). Disappearance of NH('A) occurs predominantly by the process

The process has little, if any, energy of activation, and no detectable dependence on the pressure of inert gas below 1 atm. The rate of formation of NH2 in its ground vibrational state depends on the inert gas pressure in a way that can be accounted for by vibrational relaxation from initial excited vibrational states. The total amount of NHZ is roughly comparable with the amount of HNI decomposed by primary photolysis. The observed N3 can be attributed to the NH('A) + HN3 reaction, although a smaller amount could also be formed by primary photolysis. The value of k2 is revised upward from the value given in a preliminary report on the basis of a more careful consideration of the effects of Beer's law failure in absorption measurements involving narrow spectral lines.