Ethane, dissociation excited, from

Recent investigations on ethane formation in the photolysis of acetaldehyde indicate that decomposition into methyl and formyl radicals occurs from the triplet state which is also removed by first-order internal conversion and, to some extent, by second-order deactivation. In the mercury-photosensitized reaction methyl radicals are formed by direct dissociation of the excited aldehyde molecules, as well as by collision of excited mercury atoms . 

Maricq and Szente (1995) used time resolved IR and UV spectroscopy to study the photodissociation of CF3C(0)C1 in photolysis at 193 and 248 nm. They concluded that the net reaction shown by process (III) described the results best rapidly dissociating CF3CO and/or COCl radicals presumably were present as intermediates. At 193 nm the CO is formed with extensive internal excitation (TVib = 3, 800 900 K), whereas at 248 nm it is formed predominantly in v = 0. Quantum yields of the photodecomposition were measured by comparing yields of HCl (formed in experiments with added ethane) and RO2 (experiments with added O2) from CF3C(0)C1 to those from the photodisssociation of CH3CI at 193 nm and CI2 at 248 nm they assumed the latter two species have unit photodissociation efficiencies. Values of the total quantum yield of photodecomposition, ((/>i -t- + < ) = 1.10 0.11 at 193 nm and 0.92 ... 

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