Dissociative electron attachment DEA

Dissociative electron attachment (DEA) occurs when the molecular transient anion state is dissociative in the Franck-Condon (FC) region, the localization time is of the order of or larger than the time required for dissociation along a particular nuclear coordinate, and one of the resulting fragments has positive electron affinity. In this case, a stable atomic or molecular anion is formed along with one or more neutral species. Dissociative electron attachment usually occurs via the formation of core-excited resonances since these possess sufficiently long lifetimes to allow for dissociation of the anion before autoionization. 

One often sees in the literature that one-electron reduced bases are viewed as less important in the overall scheme since they do not lead to strand breaks . It is important to note that recent studies show that low-energy electrons (<20eV) are able to produce single strand breaks in plasmid DNA by dissociative electron attachment (DEA) [8], DEA is a terminal reaction for primary and secondary electrons approaching thermal energy. It is a resonant process that leads to fragmentation at the attachment site. 

The relatively unaddressed issue is the dissociative electron attachment (DEA) involving photoexcited solvated electrons. DEA... 

The adsorbate substrate complex excitation mechanism predicts an action spectrum analagous to the absorption spectra of the complex. The direct mechanism predicts a photochemical action spectrum similar to that of the gas phase molecule. The final mechanism, dissociative electron attachment (DEA), suggests that the action spectrum should be referenced to the absorbance of the substrate, modified by the surface work function and electron attachment cross section of the adsorbate. The DEA mechanism appears to be of importance for many metal and semiconductor substrates, especially for the case of photochemistry induced by anomalously low energy radiation. 

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