A Surface Coordination Network Based on Copper Adatom Trimers

• Published in: Angewandte Chemie International Edition 2014-11, Vol.53 (47), p.12955-12959
• Main Authors: Bebensee, Fabian, Svane, Katrine, Bombis, Christian, Masini, Federico, Klyatskaya, Svetlana, Besenbacher, Flemming, Ruben, Mario, Hammer, Bjørk, Linderoth, Trolle R.
• Format: Article
• Language: English
• Subjects: Analogue; Copper; Dehydrogenation; density functional theory; Ligands; Mathematical analysis; metal-organic frameworks; Networks; Scanning tunneling microscopy; surface coordination networks; Trimers; Two dimensional; X-rays
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201406528

Surface coordination networks formed by co‐adsorption of metal atoms and organic ligands have interesting properties, for example regarding catalysis and data storage. Surface coordination networks studied to date have typically been based on single metal atom centers. The formation of a novel surface coordination network is now demonstrated that is based on network nodes in the form of clusters consisting of three Cu adatoms. The network forms by deposition of tetrahydroxybenzene (THB) on Cu(111) under UHV conditions. As shown from a combination of scanning tunneling microscopy, X‐ray photoelectron spectroscopy, and density functional theory calculations, all four hydroxy groups of THB dehydrogenate upon thermal activation at 440 K. This highly reactive ligand binds to Cu adatom trimers, which are resolved by high‐resolution STM. The network creates an ordered array of mono‐dispersed metal clusters constituting a two‐dimensional analogue of metal–organic frameworks. Cu‐trimer nodes: Using scanning tunneling microscopy and X‐ray photoelectron spectroscopy, tetrahydroxybenzene (THB) is shown to dehydrogenate when adsorbed on a Cu(111) surface and form a highly reactive ligand. Density functional calculations confirm that the ligand stabilizes copper adatom trimers and creates a surface coordination network that is a two‐dimensional analogue of metal–organic frameworks.