Methylazide photolysis at 248 nm has been investigated by ionizing photofragments with synchrotron radiation in a photofragmentation translational spectroscopy study. CH3N and N2 were the only observed primary products. The translational energy release suggests a simple bond rupture mechanism forming singlet methylnitrene, 1CH3N, and N2. Thus, these experiments reveal the unimolecular decomposition of this highly unstable species. We explain our observations through a mechanism which is initiated by the isomerization of 1CH3N to a highly internally excited methanimine H2C=NH isomer, which decomposes by 1,1-H2 elimination forming HNC+H2 as well as sequential H-atom loss (N-H followed by C-H bond cleavage), to form HCN. No evidence for dynamics on the triplet manifold of surfaces is found.
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http://dx.doi.org/10.1063/1.2215598 | DOI Listing |
J Phys Chem A
January 2025
Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.
Radical-radical reaction channels are important in the pyrolysis and oxidation chemistry of perfluoroalkyl substances (PFAS). In particular, unimolecular dissociation reactions within unbranched -perfluoroalkyl chains, and their corresponding reverse barrierless association reactions, are expected to be significant contributors to the gas-phase thermal decomposition of families of species such as perfluorinated carboxylic acids and perfluorinated sulfonic acids. Unfortunately, experimental data for these reactions are scarce and uncertain.
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Department of Chemistry, University of Hawaii, Honolulu, Hawaii, USA.
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View Article and Find Full Text PDFPhys Chem Chem Phys
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Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA.
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