title: Metal dependent motif transition in a self-assembled monolayer of bipyridine derivatives via coordination: An STM study.
abstract: Low-dimensional molecular motifs with diversity developed via the on-surface chemistry are attracting growing interest for their potential in advanced nanofabrication. In this work, scanning tunneling microscopy was employed to investigate the in situ and ex situ metal coordinations between 4,4'-ditetradecyl-2,2'-bipyridine (bpy) and Zn(ii) or Cu(ii) ions at a highly oriented pyrolytic graphite (HOPG)/1-phenyloctane interface under ambient conditions. The results demonstrate that the bpy adopts a flat-lying orientation with its substituted alkyl chains in a tail-to-tail arrangement in a bpy monolayer. For the in situ coordination, the bpy/Zn(ii) and bpy/Cu(ii) complexes are aligned in edge-on fashions, wherein the bpy stands vertically on the HOPG surface and interdigitates at the alkyl chains. In the two-dimensional arrays of ex situ coordinated complexes, metal dependent motifs have been observed with Zn(ii) and Cu(ii), wherein the bipyridine moieties are parallel to the graphite surface. These results suggest that the desired on-surface coordination architectures may be achieved by the intentional selection of the metal centers.
authors.affiliation: Laboratory of Environmental Science and Technology, The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011, China and Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Laboratory of Environmental Science and Technology, The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011, China and Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011, China.
authors.forename: Qunhui
authors.initials: Q
authors.lastname: Yuan
authors.affiliation: Laboratory of Environmental Science and Technology, The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011, China and Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011, China.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Xu
authors.affiliation: Laboratory of Environmental Science and Technology, The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011, China and Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011, China.
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Laboratory of Environmental Science and Technology, The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011, China and Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Gan