This review is devoted to trapping mass spectrometry wherein ions are confined by electromagnetic fields for prolonged periods of time within limited volume, with mass measurement taking place within the same volume. Three major types of trapping mass spectrometers are discussed, specifically radiofrequency ion trap, Fourier transform ion cyclotron resonance and Orbitrap. While these three branches are intricately interwoven with each other over their recent history, they also differ greatly in their fundamentals, roots and historical origin. This diversity is reflected also in the difference of viewpoints from which each of these directions is addressed in this review. Following the theme of the issue, we focus on developments mainly associated with the country of Germany but, at the same time, we use this review as an illustration of the rapidly increasing globalization of science and expanding multi-national collaborations.

No abstract

In Fourier transform ion cyclotron resonance mass spectrometry, simultaneous storage of positive and negative ions is possible with double well potentials. Positive and negative ions are stored in different locations of the cell (nested trap). For experiments with ion/ion reactions, positive or negative ions have to share the same region of the cell. An approximation of the potential can be used to calculate how ions can be brought together. Field-induced chaotic ion motion leads to total mixing of positive and negative ions in a suitable acceleration field.

No abstract