Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1194657 | International Journal of Mass Spectrometry | 2007 | 7 Pages |
The photoionization and dissociative photoionization of the allyl radical in the VUV range was investigated using synchrotron radiation. Allyl radicals were generated by flash pyrolysis from allyl iodide and 1,5-hexadiene. Mass spectra show the appearance of C3H3+ as a fragment in the dissociative photoionization of allyl above 10 eV. Between 10.4 and 10.5 eV the C3H3+ signal reaches 50% of its maximum value. Cyclopropenyl cation, c-C3H3+, is the thermochemically most stable product, but accompanying ab initio computations indicate that formation of linear l-C3H3+ becomes competitive at small excess energies. The dissociative photoionization of the precursor molecules is discussed as well. An ionization energy of 8.13 ± 0.01 eV was deduced from threshold photoelectron spectra.