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|Author(s):||William E. Wallace; Daniel A. Fischer;|
|Title:||Resonant Soft X-Ray Photofragmentation of Propane|
|Published:||July 01, 2003|
|Abstract:||A comparison was made between the mass spectra of propane (CH6d3^CH2CH3) for resonant soft X-ray photofragmentation and electron-impact ionization. The soft X-ray photon energy was tuned to 287.7 eV to promote Auger relaxations from the C-H bonds (1s _> C-H ς* transition). It was hypothesized that this would lead to proton loss without C-C chain fragmentation. Compared to traditional 70 eV electron-impact ionization, photoionization does bias the mass spectrum toward proton loss; however, residual vibrational energy in the room temperature propane leads to a non-trival amount of C-C bond scission. The resonant soft X-ray photofragmentation is dominated by three-carbon ions between 38 u and 40 u created by the loss of hydrogen while the electron-impact ionization is dominated by a major peak at 29 u corresponding to the two-carbon ion C2H5+. Within each envelope of three-, two-, or single-carbon ions the core-level photoionization spectrum showed a bias toward enhanced multiple hydrogen removal compared to the electron-stimulated spectrum.|
|Citation:||Journal of Electron Spectroscopy and Related Phenomena|
|Keywords:||mass spectrometry,photodissociation,photofragmentaton,photoionization,polyethylene,polymer,propane,soft x-ray,synchron|
|PDF version:||Click here to retrieve PDF version of paper (143KB)|