ISSN:
0538-8066
Keywords:
Chemistry
;
Physical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Methods are described for including the participation of bound electronically excited states in calculations on radical recombination reactions. These methods are illustrated by applying them to the reactions \documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{*{20}c} {{\rm O}\left( {^{\rm 3} P} \right)\,\, + \,{\rm O}\left( {^{\rm 3} P} \right)\,\, + \,\,{\rm M} \to {\rm O}_{{\rm 2}\,} \,\, + \,\,{\rm M}\,} \\ {{\rm O}\left( {^{\rm 3} P} \right)\,\,\, + \,\,{\rm NO}\left( {{\rm X}^{\rm 2} {\rm II}} \right)\, + \,\,{\rm M} \to {\rm NO}_{{\rm 2}\,} \,\, + \,\,{\rm M}} \\ {{\rm OH}\left( {{\rm X}^{\rm 2} {\rm II}} \right)\,\, + \,\,{\rm NO}_{\rm 2} \left( {\tilde X^2 A_1 } \right)\, + \,\,{\rm M} \to {\rm HNO}_{3\,} \,\, + \,\,{\rm M}\,\,\,} \\ \end{array} $$\end{document} For O2, accurate ab initio potentials are used in calculations which show that the electronic degeneracy and long-range part of the potential are likely to be crucial in determining the contribution of a given electronic state to the overall reaction, as long as the state is not so weakly bound that it dissociates thermally before being electronically quenched. Weak collision effects are allowed for using a Monte Carlo technique and an assumed exponential form for the distribution of energies transferred in collisions with a third body. For larger systems it is evident that the role of bound excited states in the low-pressure regime falls rapidly as the size of the system increases. As the high-pressure limit is approached, however, the contribution of excited states is likely to come close to that expected simply on the basis of electronic degeneracy.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/kin.550160411
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