Abstract
Chemical ionisation mass spectrometry of trimethylsilyl derivatives of the anions SiO4 4–, Si2O7 6–, Si3O9 6– and Si3O10 8– has been studied using isobutane as the reagent gas. The protonated molecular ion was observed in all recorded spectra. Also, the chemical ionisation spectra showed many fewer fragment peaks when compared with the corresponding electron impact spectra.