Investigating conformation dependence and nonadiabatic effects in the photodissociation of allyl chloride at 193 nm
نویسنده
چکیده
The experiments presented here investigate the competing photodissociation pathways for allyl chloride upon excitation of the nominally pp*~CvC! transition at 193 nm. The measured photofragment velocity distributions evidence C–Cl bond fission and HCl elimination. The recoil kinetic energy distribution for the HCl products is bimodal, indicating two primary processes for HCl elimination. The experimental measurements show C–Cl bond fission dominates, giving an absolute branching ratio of HCl:C–Cl50.1260.03 when the parent molecule is expanded through a nozzle at 200 °C. The branching ratio depends on the nozzle temperature; at 475 °C, the absolute branching ratio measured is HCl:C–Cl50.2460.03. We analyze the experimental results along with supporting ab initio calculations and earlier photodissociation studies of vinyl chloride in order to examine the potential influence of nonadiabaticity along the C–Cl fission reaction coordinate and its dependence on molecular conformation. © 1996 American Institute of Physics. @S0021-9606~96!01514-7#
منابع مشابه
C-Cl Bond Fission, Hcl Elimination, And Secondary Radical Decomposition In The 193 Nm Photodissociation Of Allyl Chloride
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