Two‐Dimensional Ketone‐Driven Metal–Organic Coordination on Cu(111)

Abstract

Two‐dimensional metal–organic nanostructures based on the binding of ketone groups and metal atoms were fabricated by depositing pyrene‐4,5,9,10‐tetraone (PTO) molecules on a Cu(111) surface. The strongly electronegative ketone moieties bind to either copper adatoms from the substrate or codeposited iron atoms. In the former case, scanning tunnelling microscopy images reveal the development of an extended metal–organic supramolecular structure. Each copper adatom coordinates to two ketone ligands of two neighbouring PTO molecules, forming chains that are linked together into large islands through secondary van der Waals interactions. Deposition of iron atoms leads to a transformation of this assembly resulting from the substitution of the metal centres. Density functional theory calculations reveal that the driving force for the metal substitution is primarily determined by the strength of the ketone–metal bond, which is higher for Fe than for Cu. This second class of nanostructures displays a structural dependence on the rate of iron deposition.

Collective Spin Manipulation in Antiferroelastic Spin-Crossover Metallo-Supramolecular Chains

“…As a comparison, the structures formed by continuously arranged Ni atoms in the same type showing a 1× periodicity, as highlighted by the white dashed rectangles in Figure b, are only occasionally observed as defects. The high fraction of the 2× structures distinguishes the Ni-coordinated chains achieved in this work (denoted as Ni chains hereafter) from the similar 1D structures constructed by metal atoms and THB or its analogues that all presented the 1× unit cells, as reported in previous work. − …”

“…A dehydrogenated coordination reaction of THB with Ni atoms on Au(111) upon the thermal treatment of the sample, as illustrated in Figure a, is believed to be responsible for the formation of the coordination chains. Similar on-surface reactions between various metal atoms and THB or its analogues have been documented. − …”

“…By applying the same experimental parameters that worked for the onsurface synthesis of the Ni chain, similar 1D chain structures were obtained by the coordination reaction of THB and Fe on Au(111), as shown in Figures 3a and S5a, in which the donutshaped protrusions are identified as molecular linkers while the dim dots between them as Fe atoms (denoted as Fe chain hereafter). Considering the similar reactivity of Fe and Ni 30,32 and the same experimental parameters used, we propose the same chemical bonding scenario between Fe atoms and the organic linkers with that in the Ni chain, as shown by the chemical structures superimposed in Figure 3a. The same orientations of the Fe chain and the Ni chain (the equivalent ⟨213̅ ⟩ or ⟨123̅ ⟩ directions, Figure S5a) and the identical metal−metal separation measured in the two structures (7.6 Å) indicate the same matching relationship between the chain periodicity and the substrate lattice for the Ni and Fe chains.…”

A Fundamental Role of the Molecular Length in Forming Metal–Organic Hybrids of Phenol Derivatives on Silver Surfaces

“…Gold–organic hybrids are only reported when the reaction precursor possesses multiple halogen substituents; in such, the Au–C interactions are significantly enhanced. For molecular precursors containing oxygen-based functional groups, O–Cu bonds are usually formed on copper surfaces. , On silver surfaces, interestingly, some molecules may form metal–organic hybrids while some molecules cannot. Thus, the formation mechanism of metal–organic hybrid should not be solely determined by the pairing of functional groups and metal surfaces.…”

“…After annealing at higher temperatures, all the hydrogen atoms of the hydroxyl groups are dissociated. As a result, phenols are converted into quinones. ,, Figure b gives the self-assembly structures of dehydrogenated DHBPs on a Ag(100) surface. Importantly, the flat molecular configurations are retained at this stage.…”