10.1021/ja067442g.s001 Hervé Lesnard Hervé Lesnard Marie-Laure Bocquet Marie-Laure Bocquet Nicolás Lorente Nicolás Lorente Dehydrogenation of Aromatic Molecules under a Scanning Tunneling Microscope:  Pathways and Inelastic Spectroscopy Simulations American Chemical Society 2007 5H reaction pathway yields pyridil adiabatic barriers show benzene dehydrogenation products scanning tunneling microscope phenyl 6H Inelastic Spectroscopy SimulationsWe STM pyridine 2007-04-11 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Dehydrogenation_of_Aromatic_Molecules_under_a_Scanning_Tunneling_Microscope_Pathways_and_Inelastic_Spectroscopy_Simulations/3013558 We have performed a theoretical study on the dehydrogenation of benzene and pyridine molecules on Cu(100) induced by a scanning tunneling microscope (STM). Density functional theory calculations have been used to characterize benzene, pyridine, and different dehydrogenation products. The adiabatic pathways for single and double dehydrogenation have been evaluated with the nudge elastic band method. After identification of the transition states, the analysis of the electronic structure along the reaction pathway yields interesting information on the electronic process that leads to H-scission. The adiabatic barriers show that the formation of double dehydrogenated fragments is difficult and probably beyond reach under the actual experimental conditions. However, nonadiabatic processes cannot be ruled out. Hence, in order to identify the final dehydrogenation products, the inelastic spectra are simulated and compared with the experimental ones. We can then assign phenyl (C<sub>6</sub>H<sub>5</sub>) and α-pyridil (α-C<sub>5</sub>H<sub>4</sub>N) as the STM-induced dehydrogenation products of benzene and pyridine, respectively. Our simulations permit us to understand why phenyl, pyridine, and α-pyridil present tunneling-active C−H stretch modes in opposition to benzene.