Bond dissociation and internal energies of the gas phase TiCln+ ions formed by 70 eV electron impact ionization: an ion beam study

An ion beam instrument has been constructed that utilizes a unique, simple ion deceleration lens. We demonstrate here that the kinetic energies of the ions formed can be determined accurately and precisely over a range of energies, that endothermic processes can be characterized, and that the instrument exhibits high product ion collection efficiencies. Results of collision-induced dissociation studies of the TiCl_n⁺ ions (n = 1–4), generated by 70 eV electron impact ionization, are presented here. The results are compared with those obtained from threshold measurements, and indicate that these ions are formed with substantial average internal energies. This information is useful, since the rich gas phase chemistry of TiCl_n⁺ ions with organic molecules reported to date involves reactant ions that have not been thermalized.