Transformation of pyridine to alpha-pyridyl on W(110) as probed by vibrational spectroscopy: Experiments and calculations

Using infrared spectroscopy and ab initio electronic structure calculations , we can make a conclusive assignment of the vibrational spectrum of pyridi ne adsorbed on W(110) and monitor its transformation to a-pyridyl. The assi gnments are further corroborated using isotopic N-15 vibrational shifts. We find that the pyridine molecule is already tilted edgewise prior to the tr ansformation, and both the pyridine and the alpha -pyridyl species have the ir molecular planes perpendicular to the surface.