Atom-efficient mechanisms of electron-induced chemical synthesis: Activation of CO, N2 and CO2

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Low-energy electrons with suitably selected energy (E0) interact with molecules to produce specific reactive intermediates that can initiate chemical reactions. If these reactive species do not dissociate but encounter a second reactant, synthesis of larger and more complex molecule can be the result. In the ideal case, such low-energy electron-induced synthesis is driven towards the final product by simple bond formation between the two smaller chemical precursors. These products are structurally well defined and incorporate all or most of the atoms of the precursor molecules so that the underlying reaction can be regarded as atom-efficient. As an example, electron irradiation of condensed mixtures of ethylene (C2H4) and ammonia (NH3) at E0 just above the ionization threshold induces a hydroamination reaction yielding ethylamine (CH3CHNH2). Such reactions proceed in the cation state and are thus driven by strong Coulomb forces arising after ionization and leading to attractive interactions and subsequent reaction between adjacent molecules. Another approach to prepare largely intact activated species is electron attachment without or with only minor dissociation. Such processes typically occur at near-thermal E0.The objective of this project is to use three specific small and readily available precursors, namely, CO, CO2, and N2 as building blocks for such electron-induced synthesis. The study of these reactions does not only serve to gain knowledge regarding the mechanisms of electron-induced chemistry. More importantly, such insight leads to (i) a detailed understanding of astrochemical reactions as well as (ii) to the advancement of electron-induced chemistry for a well-controlled functionalisation of materials. Another objective of the proposed project is thus to show how material science may draw advantage from the study of astrochemical processes.