Application of spectral intensities through a model potential approach to the prediction of photodissociation rate constants of CFC molecules in the ionosphere

Absorption of high-frequency radiation by chlorofluorocarbon (CFC) compounds in the ionosphere leads to their photoionization and photodissociation. Rydberg states are known to play an essential role in the initiation of photochemical processes. The photoabsorption intensities in both bound and continuous spectral regions, through all the allowed Rydberg channels, of two Freon molecules, have been first calculated. Then, through the use of the intensity data, photolysis rate constants corresponding to dissociation pathways in zones E and D of the ionosphere have been determined. An extension of the molecular quantum defect orbital approach has been used to supply these rate constants for the first time. Neither previous measurements nor theoretical calculations on these properties have, to our knowledge, been reported. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004

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