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Updated: Apr 26, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Improved ionization energies for the two isomers of phenylpropargyl radical
Fabian Holzmeier1, Melanie Lang, Patrick Hemberger
1Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg (Germany).
Abstract:
The ionization of two resonantly stabilized radicals, namely 1-phenylpropargyl (1PPR) and 3-phenylpropargyl (3PPR) are reinvestigated applying vacuum ultraviolet synchrotron radiation and threshold photoelectron spectroscopy. Ionization energies of 7.24±0.02 and 7.25±0.01 eV are obtained for 1 and 3PPR respectively, which compare well with ab initio calculations. The quality of the spectra are significantly improved mostly due to the application of a new high-photon-flux grating available at the VUV-beamline of Swiss Light Source. Resolved vibrational features are assigned according to a Franck-Condon approach.
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