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Updated: Jun 24, 2025

Using a Cyclic Ion Mobility Spectrometer for Tandem Ion Mobility Experiments
Published on: January 20, 2022
Structural analysis of C8H6˙+ fragment ion from quinoline using ion-mobility spectrometry/mass spectrometry
Kenichi Iwamoto1,2, Genki Inoue1, Hiroshi Matsubara1,2
1Department of Chemistry, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuencho Nakaku, Sakai, Osaka 599-8531, Japan. kiwamoto@omu.ac.jp.
Abstract:
This study investigated the structures of fragment ions derived from the quinoline (C9H7N) radical cation using ion-mobility spectrometry and mass spectrometry. Ion mobility and mass analysis revealed that C8H6˙+ is the primary dissociation product resulting from the loss of HCN during collision-induced dissociation of the quinoline radical cation. The reduced mobility (K0) of the C8H6˙+ fragment product in helium gas was measured over a range of reduced electric fields (E/N = 20.8-27.4 Td) at room temperature. The experimental K0 values indicated that C8H6˙+ is a mixture of phenylacetylene and pentalene radical cations. Furthermore, quantum chemical calculations revealed two potential energy surfaces delineating the loss of HCN from the quinoline radical cation to form phenylacetylene radical cations.
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