Intramolecular competition in the photodissociation of C(3)D(3) radicals at 248 and 193 nm.

  title={Intramolecular competition in the photodissociation of C(3)D(3) radicals at 248 and 193 nm.},
  author={Luca Castiglioni and Sini{\vs}a Vukovi{\'c} and Paul E. Crider and William A. Lester and Daniel M. Neumark},
  journal={Physical chemistry chemical physics : PCCP},
  volume={12 36},
Motivated by recent experimental work, a theoretical study of the photodissociation of perdeuterated propargyl (D(2)CCD) and propynyl (D(3)CCC) radicals has been carried out, focusing on the C-C bond cleavage and D(2) loss channels. High-level ab initio calculations were carried out, and RRKM rate constants were calculated for isomerization and dissociation pathways. The resulting reaction barriers, microcanonical rate constants and product branching ratios are consistent with the experimental… 

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  • W. Eisfeld
  • Chemistry
    Physical chemistry chemical physics : PCCP
  • 2005
The calculations show that the assignment of an experimentally observed absorption at 242 nm to the propargyl radical was erroneous and some recent experiments need to be re-interpreted because this absorption is due to a yet unknown species.