DETERMINATION OF BOND-DISSOCIATION ENERGIES VIA ENERGY-RESOLVED COLLISION-INDUCED DISSOCIATION IN A FOURIER-TRANSFORM ION-CYCLOTRON RESONANCE SPECTROMETER

A Fourier transform ion cyclotron resonance (ICR) spectrometer has been used to determine bond dissociation energies via translation energy controlled collisions between mass-selected ions and a stationary target gas. The ions examined were the proton-bound dimers of diethyl ether, acetone and water, which were generated in a high pressure external ion source. A comparison between bond dissociation energies obtained with this technique and literature values showed that the r.f. excitation of ions in the ICR cell produced ions with a well-defined translational energy. Moreover, the translational energy distribution of the ions was narrow, as indicated by the fact that experimentally obtained threshold curves for dissocation were close to computed curves corrected for Doppler broadening.