title: VUV photoionization and dissociative photoionization of the prebiotic molecule acetyl cyanide: theory and experiment.
abstract: The present combined theoretical and experimental investigation concerns the single photoionization of gas-phase acetyl cyanide and the fragmentation pathways of the resulting cation. Acetyl cyanide (AC) is inspired from both the chemistry of cyanoacetylene and the Strecker reaction which are thought to be at the origin of medium sized prebiotic molecules in the interstellar medium. AC can be formed by reaction from cyanoacetylene and water but also from acetaldehyde and HCN or the corresponding radicals. In view of the interpretation of vacuum ultraviolet (VUV) experimental data obtained using synchrotron radiation, we explored the ground potential energy surface (PES) of acetyl cyanide and of its cation using standard and recently implemented explicitly correlated methodologies. Our PES covers the regions of tautomerism (between keto and enol forms) and of the lowest fragmentation channels. This allowed us to deduce accurate thermochemical data for this astrobiologically relevant molecule. Unimolecular decomposition of the AC cation turns out to be very complex. The implications for the evolution of prebiotic molecules under VUV irradiation are discussed.
authors.affiliation: Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, Université Paris-Est, 5 bd Descartes, 77454 Marne-la-Vallée, France.
authors.forename: A
authors.initials: A
authors.lastname: Bellili
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR 7583 CNRS, Institut Pierre et Simon Laplace, Universités Paris-Est Créteil et Paris Diderot, 61 Avenue du Général de Gaulle, 94010 Créteil, France.
authors.forename: M
authors.initials: M
authors.lastname: Schwell
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR 7583 CNRS, Institut Pierre et Simon Laplace, Universités Paris-Est Créteil et Paris Diderot, 61 Avenue du Général de Gaulle, 94010 Créteil, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Bénilan
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR 7583 CNRS, Institut Pierre et Simon Laplace, Universités Paris-Est Créteil et Paris Diderot, 61 Avenue du Général de Gaulle, 94010 Créteil, France.
authors.forename: N
authors.initials: N
authors.lastname: Fray
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR 7583 CNRS, Institut Pierre et Simon Laplace, Universités Paris-Est Créteil et Paris Diderot, 61 Avenue du Général de Gaulle, 94010 Créteil, France.
authors.forename: M-C
authors.initials: MC
authors.lastname: Gazeau
authors.affiliation: Chemistry Department, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Kingdom of Saudi Arabia.
authors.forename: M
authors.initials: M
authors.lastname: Mogren Al-Mogren
authors.affiliation: Institut des Sciences Chimiques de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France.
authors.forename: J-C
authors.initials: JC
authors.lastname: Guillemin
authors.affiliation: Laboratoire Francis Perrin, CNRS URA 2453, CEA, IRAMIS, Laboratoire Interactions Dynamique et Lasers, Bât 522, F-91191 Gif/Yvette, France.
authors.forename: L
authors.initials: L
authors.lastname: Poisson
authors.affiliation: Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, Université Paris-Est, 5 bd Descartes, 77454 Marne-la-Vallée, France.
authors.forename: M
authors.initials: M
authors.lastname: Hochlaf
mesh_terms: D000079:Acetaldehyde / Q000737:chemistry; D000107:Acetylation; D000114:Acetylene / Q000031:analogs & derivatives* / Q000737:chemistry; D002412:Cations / Q000737:chemistry*; D003486:Cyanides / Q000737:chemistry*; D005118:Extraterrestrial Environment / Q000737:chemistry*; D008958:Models, Molecular; D009570:Nitriles / Q000737:chemistry*; D014466:Ultraviolet Rays; D014618:Vacuum; D014867:Water / Q000737:chemistry
chemical_list: D002412:Cations; D003486:Cyanides; D009570:Nitriles; C513097:cyanoacetylene; D014867:Water; D000079:Acetaldehyde; D000114:Acetylene