Ion-molecule surface reactions induced by slow (5<i>–</i>20 eV) electrons

Abstract

Electron-stimulated desorption of ${\mathrm{H}}^{\mathrm{\ensuremath{-}}}$, ${\mathrm{O}}^{\mathrm{\ensuremath{-}}}$, and ${\mathrm{OH}}^{\mathrm{\ensuremath{-}}}$ ions from a metal-deposited multilayer ${\mathrm{O}}_{2}$ film covered with ${\mathrm{C}}_{\mathrm{n}}$${\mathrm{H}}_{2\mathrm{n}+2}$ molecules is reported for the incident energy range 5--20 eV. By producing selectively with the electron beam ${\mathrm{O}}^{\mathrm{\ensuremath{-}}}$${(\mathrm{}}^{2}$P) ions on the film, via the dissociative attachment reaction ${\mathrm{O}}_{2}$${(}^{3}$${\mathrm{\ensuremath{\Sigma}}}_{\mathrm{g}}^{\mathrm{\ensuremath{-}}}$)+${\mathrm{e}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\mathrm{O}}_{2}^{\mathrm{\ensuremath{-}}}$${(}^{2}$${\mathrm{\ensuremath{\Pi}}}_{\mathrm{u}}$${,}^{2}$${\mathrm{\ensuremath{\Sigma}}}_{\mathrm{g}}^{+}$) \ensuremath{\rightarrow}${\mathrm{O}}^{\mathrm{\ensuremath{-}}}$${(\mathrm{}}^{2}$P)+O${(\mathrm{}}^{3}$P), the surface reaction ${\mathrm{O}}^{\mathrm{\ensuremath{-}}}$+${\mathrm{C}}_{\mathrm{n}}$${\mathrm{H}}_{2\mathrm{n}+2}$\ensuremath{\rightarrow}${\mathrm{OH}}^{\mathrm{\ensuremath{-}}}$ +${\mathrm{C}}_{\mathrm{n}}$${\mathrm{H}}_{2\mathrm{n}+1}$ can be induced and controlled.