title: Formation of unique trimer of nitric oxide on Cu(111).
abstract: We report that NO molecules unexpectedly prefer a trimeric configuration on Cu(111). We used scanning tunneling microscopy (STM) at 6 K, and confirmed that the NO molecule is bonded to the face-centered-cubic hollow site in an upright configuration. The individual NO molecule is imaged as a ring protrusion, which is characteristic of the doubly degenerate 2π(*) orbital. A triangular trimer is thermodynamically more favorable than the monomer and dimer, and its bonding structure was characterized by STM manipulation. This unique behavior of NO on Cu(111) is ascribed to the threefold symmetry of the surface, facilitating effective mixing of the 2π(*) orbitals in a triangular configuration.
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Shiotari
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Hatta
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Okuyama
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Aruga
mesh_terms: D000327:Adsorption; D003300:Copper / Q000737:chemistry*; D016252:Microscopy, Scanning Tunneling; D009569:Nitric Oxide / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D009569:Nitric Oxide; D003300:Copper