Evidence for sequential reactions in the CO2 laser induced multiphoton dissociation of acetic anhydride and acetic acid

The CO2 laser induced multiphoton dissociation of acetic acid and acetic anhydride has been investigated. We have observed the prompt formation of 1CH2 and OH by laser excited fluorescence and determined their nascent rotational energy distributions. The rotational energy of each product was the same, regardless of which starting material was photolyzed. This observation leads us to propose a mechanism in which both the 1CH2 and the OH are formed by sequential up‐pumping of molecular intermediates. We have also determined the yield versus fluence curves for both the a (0,0,0) and a (0,1,0) levels of 1CH2. The relative yields of these two levels are found to change as a function of intensity.

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