Open AccessDissociation dynamics of phenetole cations by photoelectron photoion coincidence
Author(s) -
John S. Riley,
Tomas Baer
Publication year - 1991
Publication title -
journal of the american society for mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.961
H-Index - 127
eISSN - 1879-1123
pISSN - 1044-0305
DOI - 10.1016/1044-0305(91)80032-3
Subject(s) - chemistry , dissociation (chemistry) , ion , mass spectrometry , analytical chemistry (journal) , activation energy , atomic physics , photochemistry , organic chemistry , chromatography , physics
The dissociation rates of phenetole ions have been measured as a function of the ion internal energy by the method of photoelectron photoion coincidence spectrometry. The loss of ethylene to produce the phenol ion is the only dissociation pathway from its onset at 9.17 eV up to at least 12 eV. An activation energy of 1.64 ± 0.06 eV with an assumed activation entropy of + 18 ± 4 cal/mol-K is derived from fitting the statistical theory decay rates to the measured rates. The transition state energy lies ∼ 1 eV below the thermochemical dissociation limit to the C2H 5 (+) + C6H5O · products. It is thus unlikely that an ion-radical complex is involved in the production of the phenol ion.