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Collisionally induced dissociative ionization of neutral products from ion fragmentations. 2—Collision gas effects and related phenomena
Author(s) -
Clair Roberta,
Holmes John L.,
Mommers Alexander A.,
Burgers Peter C.
Publication year - 1985
Publication title -
organic mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.475
H-Index - 121
eISSN - 1096-9888
pISSN - 0030-493X
DOI - 10.1002/oms.1210200308
Subject(s) - fragmentation (computing) , chemistry , ion , mass spectrum , collision induced dissociation , ionization , mass spectrometry , electron ionization , dissociation (chemistry) , atomic physics , collision , analytical chemistry (journal) , tandem mass spectrometry , physics , chromatography , computer security , organic chemistry , computer science , operating system
The ion retardation method (whereby an ion beam is prevented from entering a collision gas cell by means of a voltage applied thereto) for permitting the examination of the neutral products of unimolecular ion fragmentations has been extended to include observations of neutral products generated by collisions before the gas cell and their related phenomenology. Observations obtained using an ion beam deflection electrode, an alternative method of preventing the ion beam from entering the collision cell, are also reported. When low collision gas pressures are employed (<2×10 −7 Torr He), this latter method provides collisionally induced dissociative ionization (CIDI) mass spectra of unimolecularly generated neutral fragmentation products, free of complications arising from events induced by collisions occurring outside the collision cell. The CIDI mass spectra of CH 3 ˙, C 2 H 4 , CH 3 ĊO, CH 3 OH and C 2 H 6 generated from positive ion precursors and CH 3 ˙, CH 3 O˙ and C 6 H 5 NO 2 generated by electron loss from negative ions are described.