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Excitation in ion–molecule collisions. A study of protonated aromatic molecules by ion kinetic energy spectrometry
Author(s) -
Franchetti V.,
Freiser B. S.,
Cooks R. G.
Publication year - 1978
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.1210130208
Subject(s) - dissociation (chemistry) , photoexcitation , photodissociation , ion , chemistry , electron ionization , kinetic energy , mass spectrometry , fragmentation (computing) , collision induced dissociation , ionic bonding , molecule , protonation , ionization , mass spectrum , excitation , atomic physics , photochemistry , tandem mass spectrometry , excited state , physics , organic chemistry , quantum mechanics , chromatography , computer science , operating system
Collision induced dissociation of protonated aromatic ions formed in a chemical ionization source has been studied using the technique of mass analyzed ion kinetic energy spectrometry. The observed fragmentations are concordant with those seen in the photodissociation spectra of the same ions with one significant exception. Loss of H is always a major collision induced dissociation process but is not observed in photodissociation spectra. This differences is not due to differences in the total amount of energy transferred in ionic excitation but to differences in the form in which the energy is supplied. Collision induced dissociation can lead to processes forbidden in photoexcitation, particularly those associated with electron unpairing in violation of the even→even+even rule for fragmentations.