The influence of spontaneous m/z-changes on the ion motion in an ion cyclotron resonance trap

The influence of mass-over-charge ratio (m/z) changing reactions on the motion of stored ions in a Penning trap (ion cyclotron resonance cell) is investigated. For all three motional modes, the cyclotron, the magnetron and the axial (trapping) motion, the influence of the m/z change on the amplitude is discussed. In cases of spontaneous m/z increase, as for electron loss from a polyanionic particle, the extension of the radial ion motion is increased and thus the ions may be lost from the trap. As an example, measurements on the electron emission from doubly charged cluster anions are discussed.