Accession Number : AD0763755

Title :   Chemiluminescent Gas Phase Reactions of Ozone with Selected Olefins.

Descriptive Note : Technical rept.,

Corporate Author : CALIFORNIA UNIV RIVERSIDE INST OF GEOPHYSICS AND PLANETARY PHYSICS

Personal Author(s) : Pitts,James N. , Jr. ; Finlayson,Barbara J.

Report Date : 01 JUL 1973

Pagination or Media Count : 333

Abstract : Detailed studies have been performed on the chemiluminescent gas phase reactions of ozone with selected olefins at room temperature from 2 to 10 torr. HCHO and OH (Meinel Bands) were the emitting species common to all ozone-olefin reactions studied, both in the presence and absence of oxygen. A peak at 520 nm in the cis-2-butene-ozone reaction was tentatively identified as glyoxal phosphorescence while a peak at 517 nm in the isobutene, trimethylethylene or tetramethylethylene reactions with ozone in oxygen remains unidentified. The chemiluminescence quantum yield for formaldehyde fluorescence in the ethylene and cis-2-butene reactions was estimated. A high yield of OH calculated from the total rate of light emission implies that an unknown chain mechanism for its production must be operative. In the cis-2-butene reaction with ozone, the radicals HCO, C2H5, HO2, C2H5O and CH3O2 the stable or labile products CH3CHO, CH2CO, HCHO, H2O2, CH3OH, HCOOH, (CHO)2 were identified. The observations of radicals in the low pressure gas phase pzone-olefin reactions necessitate a re-examination of the exclusive application of the Criegee mechanism of ozonolysis to the gas phase studies. (Modified author abstract)

Descriptors :   (*CHEMILUMINESCENCE, *OZONE), (*ALKENES, CHEMILUMINESCENCE), FREE RADICALS, PHOTOCHEMICAL REACTIONS, MOLECULAR ENERGY LEVELS, EXCITATION, REACTION KINETICS

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE