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Published on: August 19, 2013
Vacuum Ultraviolet Fingerprints as a New Way of Disentangling Tropylium/Benzylium Isomers
Corentin Rossi1, Bérenger Gans1, Alexandre Giuliani2,3
1Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay, 91405 Orsay, France.
Abstract:
The two inseparable companions, tropylium (Tr+) and benzylium (Bz+), were interrogated by vacuum ultraviolet (VUV) radiation from 4.5 to 7.0 eV in an ion trap. These new fingerprints provide a new means of distinguishing these two intertwined C7H7+ isomers. In particular, the singular spectral signature of Tr+ in the VUV consists of a single strong electronic transition at ≈6 eV. To illustrate this diagnostic tool, we shed light on the structure of the C7H7+ intermediate that is ubiquitous when using commercial atmospheric pressure photoionization (APPI) sources. We have identified its structure as the 7-membered ring Tr+, which contradicts some previous beliefs.
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