Autocatalytic Dissociative Adsorption of Imidazole on the Ge(100)-2 × 1 Surface

Abstract

The adsorption of imidazole on the Ge(100)-2 × 1 surface is studied with ultrahigh vacuum infrared spectroscopy experiments and density functional theory calculations. Imidazole datively bonds to the surface through its pyridinic nitrogen at low coverage, while dissociation of the pyrrolic N–H is observed upon larger exposure. The coverage-dependent change in the product distribution is explained by autocatalytic activation of the dissociative adsorption via interaction between adjacent imidazole adsorbates. These results suggest an alternative explanation for the previously studied adsorption chemistry of bifunctional ethylenediamine on Ge(100)-2 × 1.

Thermally Activated Reactions of Phenol at the Ge(100)-2 × 1 Surface

“…Various aromatic molecules’ adsorption chemistry has been studied on the Ge(100) surface. − Unlike on reactive surfaces of catalytic metals such as Ni or Pt at which molecular decomposition readily occurs, , the aromaticity of the molecules on Ge is often well preserved upon adsorption due to the moderate reactivity of the surface . Even in some examples such as adsorption of nitrobenzene (C 6 H 5 –NO 2 ) and phenyl isocyanate (C 6 H 5 –NCO) on Ge(100), in which post-adsorption transformation of the molecular structure was found, an intact phenyl (C 6 H 5 – ) moiety was observed as part of the final reaction product. , The adsorption product of phenol (C 6 H 5 –OH) on Ge(100) at room temperature also has been reported as a surface phenoxy moiety (C 6 H 5 O*), formed by a proton transfer reaction to the Ge surface dimer …”