title: Direct observation of size dependent activation of NO on gold clusters.
abstract: Vibrational spectra of NO ligands adsorbed on cationic gold clusters are obtained using IR multiphoton dissociation spectroscopy. We observe a strong oscillation of the NO stretching frequency with increasing cluster size that reveals a clear odd-even dependence in the strength of the NO bond. For the corresponding CO complexes, no oscillation is found. This behaviour can be understood on the basis of the character and occupation of the frontier orbitals of the complexes.
authors.affiliation: Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany. fielicke@fhi-berlin.mpg.de
authors.forename: André
authors.initials: A
authors.lastname: Fielicke
authors.forename: Gert
authors.initials: G
authors.lastname: von Helden
authors.forename: Gerard
authors.initials: G
authors.lastname: Meijer
authors.forename: Benoit
authors.initials: B
authors.lastname: Simard
authors.forename: David M
authors.initials: DM
authors.lastname: Rayner
mesh_terms: D002248:Carbon Monoxide / Q000737:chemistry; D002384:Catalysis; D002412:Cations; D006046:Gold / Q000737:chemistry*; D008024:Ligands; D008670:Metals / Q000737:chemistry; D008956:Models, Chemical; D008968:Molecular Conformation; D009569:Nitric Oxide / Q000737:chemistry*; D009991:Oscillometry / Q000379:methods; D010100:Oxygen / Q000737:chemistry; D013053:Spectrophotometry / Q000379:methods; D013055:Spectrophotometry, Infrared / Q000379:methods; D013696:Temperature
chemical_list: D002412:Cations; D008024:Ligands; D008670:Metals; D009569:Nitric Oxide; D006046:Gold; D002248:Carbon Monoxide; D010100:Oxygen