A near edge X-ray absorption fine structure study of the adsorption of pyrrole and N-methylpyrrole on Pt(111): Orientation and dissociation of the adsorbed molecules

摘要: Abstract The adsorption of the planar heterocyclic molecules pyrrole (C 4 NH 5 ) and N-methylpyrrole 7 on Pt(111) has been studied with near edge X-ray absorption fine structure (NEXAFS). Polarization dependent NEXAFS spectra were obtained above nitrogen K-edge both after initial deposition at 84 K following annealing treatments. With annealing, polarization dependence N shows that becomes oriented molecular plane normal to surface, whereas remains orientationally disordered. Continued however, resulting in lower surface coverages, induces an orientational disordering a further dissociation into N-containing species which remain surface. is found be more stable respect dissociation, likely simply desorb.