INVESTIGATION OF THE MASS SHIFTS CAUSED BY THE COUPLING OF ION MOTIONS IN THE ION-TRAP MASS-SPECTROMETER

An ion-coupling model has been proposed to predict and interpret the o ccurrence of mass shifts induced by the presence of ions of other m/z ratios in the ion trap mass spectrometer. The method of dynamically sc anning the dipolar tickle frequency has been used to determine the mas s shifts for two species of ions involved in a coupling interaction. T he experimental results, together with the evidence found in published spectra, provide a fair support of the existence of ion-coupling effe cts which give rise to a subsequent mass shift. The ion-coupling pheno menon is expected to arise whenever more than one species of ion is tr apped.