Internal energy randomisation in weak-collision unimolecular reaction systems

Abstract

H. 0. PRITCHARD and S. R. VATSYA. Can. J. Chem. 59, 2575 (1981). We examine the conjecture that the principal difference between weak-collision and strong-collision behaviour in thermal unimolecular reaction systems arises from a difference in internal energy randomisation rates. To do this, we solve analytically the strong-collision master equation for a thermal unimolecular reaction including explicit allowance for the randomisation processes, and we show that all weak-collision effects so far observed in thermal systems can be accommodated within this framework.In an appendix, we give the extension of this analytic solution for reactions yielding two (or more) distinct sets of products. Nous examinons I'hypothese relative au fait que la difference principale de comportement entre une collision faible et collision forte, dans les systkmes de reactions thermique unimolCculaire, provient de la difference entre les vitesses de distribution au hasard de I'energie interne. Pour ce faire nous rCsolvons analytiquement I'tquation principale de collision forte pour une reaction thermique unimolCculaire incluant une correction explicite pour le processus de distribution au hasard, et nous montrons que tous les effets de collision faible observes dans les systkmes thermiques peuvent s'integrer dans ce cadre.En appendice nous donnons le dkveloppement de cette solution analytique pour les reactions conduisant a deux (ou plus) ensembles distincts de produits.[Traduit par le journal]

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