A long-range ordered array of copper tetrameric units embedded in an on-surface metal organic framework

Abstract

We report on the assembly of a highly ordered array of copper tetrameric clusters, coordinated into a metal-organic network. The ordered cluster array has been achieved by the deposition of tetrahydroxyquinone molecules on the Cu(111) surface at room temperature, and subsequent thermally activated dehydrogenation with the formation of tetraoxyquinone tetra-anions with a 4 × 4 periodicity. The supramolecular organic network acts as a spacer for the highly ordered two-dimensional network of copper tetramers at the very surface.

Copper-assisted oxidation of catechols into quinone derivatives

“…Two-component spectra of this kind have been assigned to the coexistence of an alcohol function (532–533 eV) and a ketone function (∼531 eV) in related molecules deposited on various metal surfaces. 30–32,36–39 NEXAFS spectra display signature of an electronic transition towards a CC–CO orbital 40 (see ESI, Fig. S13†), which supports this interpretation.…”

“…S10 †), 34,35 usually being grouped into a single component. [30][31][32][33] In contrast, profound changes are found in the O 1s spectra (Fig. 2).…”

“…Our XPS measurements reveal qualitatively similar C 1s spectra before/aer annealing to 530 K, which seem to comprise (at least) three components, ascribed to C atoms bond to Ocontaining groups (285.7/285.5 eV), to H atoms in the three outer rings (284.7/284.4 eV), and to C atoms in the central ring (284.2/284.0 eV). [30][31][32][33] In fact, the highest-energy component, corresponding to chemically inequivalent C atoms bound to alcohol or ketone groups, comprise two contributions, which are typically separated by only 0.2 eV from one another (see ESI, Fig. S10 †), 34,35 usually being grouped into a single component.…”

On‐surface Synthesis of a Semiconducting 2D Metal–Organic Framework Cu3(C6O6) Exhibiting Dispersive Electronic Bands

“…The green peak at higher binding energy is in excellent agreement with reported values of intact aryl alcohols adsorbed on Cu(111) . The red peak at the lower binding energy marks a chemical change of the aryl alcohol which can be ascribed to a substrate stabilized O anion/O radical or a ketone strongly interacting with the Cu(111) . It is noteworthy that the O 1s spectrum matches perfectly the reported one of intact tetrahydroxyquinone (THQ) on Cu(111) .…”

“…The red peak at the lower binding energy marks a chemical change of the aryl alcohol which can be ascribed to a substrate stabilized O anion/O radical or a ketone strongly interacting with the Cu(111) . It is noteworthy that the O 1s spectrum matches perfectly the reported one of intact tetrahydroxyquinone (THQ) on Cu(111) . The C 1s signature reveals that the C atoms of the molecule (Supporting Information, Figure S3) are chemically equivalent.…”