2970
J. Phys. Chem. A 2006, 110, 2970-2978
Structural Aspects of Long-Lived C7H82+ Dications Generated by the Electron Ionization of Toluene† Jana Roithova´ ,*,‡,§ Detlef Schro1 der,*,§ Philipp Gruene,§ Thomas Weiske,§ and Helmut Schwarz§ J. HeyroVsky´ Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, DolejsˇkoVa 3, 18223 Praha 8, Czech Republic, and Institut fu¨r Chemie der Technischen UniVersita¨t Berlin, Straβe des 17. Juni 135, D-10623 Berlin, Germany ReceiVed: August 12, 2005; In Final Form: October 19, 2005
The structure of the C7H82+ dication generated upon electron ionization of toluene is investigated by experimental and theoretical means. For the long-lived C7H82+ dication, the experimental findings obtained with a novel SIFT/GIB instrument suggest complete loss of structural integrity corresponding to the toluene structure. Instead, the manifold of C7H82+ dications most likely to be formed is assigned to a mixture of the cycloheptatriene dication and ring-protonated benzylium ions.
Introduction The structure and fragmentation patterns of neutral1,2 and ionized3 toluene have been extensively studied in the past. The structure of the C7H8•+ ions formed by the ionization of toluene depends on the internal energy deposited in the course of ionization.4 Thus, at low internal energies (
