Some characteristics of a venetian blind particle multiplier used as a detector in the study of ion-molecule reactions

A venetian blind particle multiplier has been examined to test its suitability for use in the measurement of ion-molecule specific reaction rates. Considerable variations in some of the characteristics of the multiplier have been observed over a period of several months. Nevertheless in a series of ion-molecule reactions of the type XH⁺ + XH -> XH₂⁺ + X the specific reaction rate measured by means of the multiplier agreed well with the same rates measured with a Faraday cup detector. Thus chemical discrimination effects which have been observed with electrostatically focused multipliers were not observed with this instrument.