Computer modelling of fragmentation processes in radio frequency multipole collision cells

To date, methods for calculating the trajectories of ions in radio frequency (RF) multipole fields have involved solving, analytically or numerically, the appropriate equations of motion. Another method is presented here whereby a non‐ideal distribution of field may be modelled and the position of an ion can be tracked, as it traverses the multipole. The validity of the calculations is discussed and some of the properties of collision cells are explained. Fragmentation processes within the cell are modelled showing that the focusing properties within the cell have a striking effect on parent‐ and daughter‐ion transmission.