Simulation of electron impact mass spectra by charge exchange in chemical ionization mass spectrometry

Gas chromatographic sample introduction into the collision cell of a triple quadrupole mass spectrometer for mass-selection of reactant ions for charge exchange and chemical ionization

“…Charge exchange ionization produces odd-electron species as does El (31, 32). It has previously been shown that CE spectra can be searched against the NBS El library with acceptable results (32). These concepts were investigated by using mass-selected reactions in the TQMS.…”

Chemical ionization in an ion trap mass spectrometer

“…Ionization based on reactions other than proton transfer has also been investigated. When proton transfer agents such as methane do not yield fragmentation which allow meaningful spectral interpretation, an alternative ionization method is charge exchange (35)(36)(37). The types of fragments observed are controlled by the fact that the radical cation is generated, and the degree of dissociation is determined, by the difference in energy between the recombination energy of the reagent and the ionization potential of the sample molecule.…”

Electron-ionization-like mass spectra by capillary supercritical fluid chromatography/charge exchange mass spectrometry

“…Most data presented from SFC/MS experiments have been obtained by using conventional chemical ionization (Cl) methods (2, [5][6][7][8] with the exception of a few examples of electron ionization (El) (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). This is primarily due to the decrease in sensitivity achieved for El SFC/MS compared to that of El GC/MS for similar compounds.…”

“…Advances in this area in the past few years have included the use of high-speed mechanical valves or fluid logic gates (2)(3)(4)(7)(8)(9)(10)(11). The use of cold trapping for the collection of airborne samples and the rapid reinjection of collected vapor or liquid samples has also resulted in the development and investigation of many effective systems (6,(12)(13)(14)(15)(16)(17)(18)(19)(20)(21).…”