Spectroscopic Studies of Reactive Intermediates in the Chemistry of

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Spectroscopic Studies of the Chemistry of Ozone: Applications to
Atmospheric Chemistry and Semiconductors
Bruce S. Ault
Department of Chemistry
University of Cincinnati
Cincinnati, OH 45221-0172
Abstract
The reaction of ozone with alkenes is a principal route to the removal of these
volatile organic compounds from the atmosphere. For 50 years, indirect evidence
supporting the Criegee mechanism for this reaction has accumulated, yet the principal
intermediates have not been observed. Also, O3 is beginning to see application as an
oxygen source in the chemical vapor deposition of metal oxide thin films through
reaction with appropriate organometallic compounds. However, very little is known
about the mechanistic details of the reactions leading to thin film formation. The matrix
isolation technique, operating near 12 K, is uniquely suited for the isolation,
identification and characterization of a wide range of reactive intermediates. Different
methods may be used to deposit matrices, thereby allowing control over the time
available for reaction between the precursors, as well as the available energy. Theoretical
calculations using ab initio and density functional methods provide a powerful
complement to the experimental studies. Using these approaches, the sequence of
intermediates in the reactions of O3 with alkenes and organometallic compounds will be
discussed.
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