The energy dispersion effect in field ionization/field desorption quadrupole mass spectrometers

Abstract

A method is described whereby field ionization/field desorption quadrupole mass spectrometers can be used for energy analysis and appearance potential determination of field ions. With this method no special instrumental modifications are necessary. When employed for measurements of ionization potentials of some rare gases and some organic molecules an accuracy of better than +or-0.2 eV could be achieved when Pt tips were used as field anodes. The accuracy of measurement decreased only slightly when field ionization was performed at high temperature activated tungsten wire emitters. The same method of measurement also could be applied successfully to ions generated by field desorption.