Electron Attachment to Excited Molecules
Studies on electron attachment to molecules rotationally/vibrationally excited thermally or via infrared-laser excitation showed that the effect of internal energy of a molecule on its electron attachment properties depends on the mode-dissociative or nondissociative-of electron attachment. They quantified the effect of the internal energy of the molecule on the rate of destruction (by autodissociation or by autodetachment) of its parent transient anion. Generally, increases in ro-vibrational molecular energy increase the cross section for dissociative electron attachment and decrease the effective cross section for parent anion formation due mainly to increased autodetachment. These findings and their understanding are discussed. A discussion is given, also, of recent investigations of electron attachment to electronically excited molecules, especially photoenhanced dissociative electron attachment to long- and short-lived excited electronic states of molecules produced directly or indirectly by laser irradiation. These studies showed that the cross sections for dissociative electron attachment to electronically excited molecules usually are many orders of magnitude larger than those for the ground-state molecules. The new techniques that have been developed for such studies are briefly described also.
KeywordsMicrowave Polycyclic Aromatic Hydrocarbon Disulfide Benzoquinone Deuterium
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