Selective adsorption of a supramolecular structure on flat and stepped gold surfaces

SURFACE SCIENCE

卷:670

Article

Pekoz, Rengin¹  Donadio, Davide^2,3,4 

[1] Atilim Univ, Dept Elect & Elect Engn, TR-06836 Ankara, Turkey

[2] Univ Calif Davis, Dept Chem, One Shields Ave, Davis, CA 95616 USA

[3] Max Planck Inst Polymer Res, Ackermannweg 10, D-55128 Mainz, Germany

[4] Basque Fdn Sci, Ikerbasque, E-48011 Bilbao, Spain

关键词: Metal-organic interfaces;    Density functional theory;    Dispersion forces;    Self assembly;   

DOI  :  10.1016/j.susc.2017.12.010

来源: Elsevier

【 摘 要 】

Halogenated aromatic molecules assemble on surfaces forming both hydrogen and halogen bonds. Even though these systems have been intensively studied on flat metal surfaces, high-index vicinal surfaces remain challenging, as they may induce complex adsorbate structures. The adsorption of 2,6-dibromoanthraquinone (2,6-DBAQ) on flat and stepped gold surfaces is studied by means of van der Waals corrected density functional theory. Equilibrium geometries and corresponding adsorption energies are systematically investigated for various different adsorption configurations. It is shown that bridge sites and step edges are the preferred adsorption sites for single molecules on flat and stepped surfaces, respectively. The role of van der Waals interactions, halogen bonds and hydrogen bonds are explored for a monolayer coverage of 2,6-DBAQ molecules, revealing that molecular flexibility and intermolecular interactions stabilize two-dimensional networks on both flat and stepped surfaces. Our results provide a rationale for experimental observation of molecular carpeting on high-index vicinal surfaces of transition metals. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

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