a compact high pressure ion source for high and low energy collision-induced dissociation studies of cluster ions on a VG analytical ZAB-2FQ.

A compact, field-free high pressure ion source designed to replace, with minimum disruption, the electron impact/chemical ionization ion source of a VG Analytical ZAB-2FQ hybrid BEqQ mass spectrometer is described. This ion source may be operated at temperatures from ≈40 to 250 °C and at pressures up to 4-5 torr and, thus, is capable of producing proton-bound cluster ions up to hexamers in good yields. Examples of high energy collision-induced dissociation, low energy collision-induced dissociation, and neutralization-reionization studies of proton-bound cluster ions produced in this source are presented.