Low-energy electrons (Ei < 30 eV) play a major role in many different applications and techniques such as plasma chemistry, radiation chemistry and biology, particle beam and photon induced surface chemistry [1]. Upon interaction with condensed molecules, electrons drive bond cleavage thus generating a population of very reactive species in the condensed medium. These species may interact either within the film to synthesize new molecules or form a chemical bond with the substrate surface. The former reaction is known as electron-induced synthesis [2] and the latter as electron-induced surface functionalization [3]. In the case of high-energy electrons the chemical specificity is low due to the large number of dissociative open channels. In contrast electrons with energies below ionization threshold of the exposed matter are capable of selective bond cleavage associated with Dissociative Electron Attachment (DEA) mechanism. DEA implies the formation of a transient negative ion that can be viewed as a molecular quantum state embedded in the electron-target continuum. Electron interaction with condensed molecules on hydrogenated diamond substrate will be discussed. In particular, electron induced functionalization of diamond surfaces by CH2CN groups, decarboxylation reactions in condensed films of pure organic acids RCOOH (R = H, CH3, C2H5, CF3), and carbamic acid formation in CO2:NH3 binary ice mixtures will be discussed.
[1] A. Lafosse, M. Bertin, R. Azria, Progress Surf. Sci. 84 (2009) 177-198, and references therein.
[2] I. Bald, J. Langer, P. Tegeder, O. Ing—lfsson, Int. J. Mass Spectrom. 277 (2008) 4.
[3] Y. Chen et al., Phys. Rev. B 43 (1991) 4527; W. Di, P. Rowntree, L. Sanche, Phys. Rev. B 52 (1995) 16618; D.V. Klyachko, P. Rowntree, L. Sanche, Surf. Sci. 389 (1997) 29.
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