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Updated: Aug 2, 2026

Analysis of Volatile and Oxidation Sensitive Compounds Using a Cold Inlet System and Electron Impact Mass Spectrometry
Published on: September 5, 2014
One-color two-photon mass-analyzed threshold ionization spectroscopy of ethyl bromide through a dissociative
Bifeng Tang1, Song Zhang, Yanmei Wang
1State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, People's Republic of China.
Abstract:
Mass-analyzed threshold ionization (MATI) spectra of ethyl bromide were obtained using one-color two-photon ionization through a dissociative intermediate state. Accurate values for the adiabatic ionization energy have been obtained, 83099+/-5 and 85454+/-5 cm(-1) for the X1 2E and X2 2E states of the ethyl bromide cation, respectively, giving a splitting of 2355+/-10 cm(-1). Compared with conventional photoelectron data, the two-photon MATI spectrum exhibited a more extensive vibrational structure with a higher resolution, mainly containing the modes involving the dissociation coordinate. The observed modes were analyzed and discussed in terms of wave packet evolving on the potential-energy surface of the dissociative state.
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