Diboraperylene diborinic acid self-assembly on Ag(111)—kagome flat band localized states Imaged by scanning tunneling microscopy and spectroscopy
Angew. Chem. Int. Ed., 63 (15):
e202400313 (Feb 5, 2024)DOI: https://doi.org/10.1002/anie.202400313
Abstract
Abstract Replacement of sp2-hybridized carbon in polycyclic aromatic hydrocarbons (PAHs) by boron affords electron-deficient π-scaffolds due to the vacant pz-orbital of three-coordinate boron with the potential for pronounced electronic interactions with electron-rich metal surfaces. Using a diboraperylene diborinic acid derivative as precursor and a controlled on-surface non-covalent synthesis approach, we report on a self-assembled chiral supramolecular kagome network on an Ag(111) surface stabilized by intermolecular hydrogen-bonding interactions at low temperature. Scanning tunneling microscopy (STM) and spectroscopy (STS) reveal a flat band at ca. 0.33?eV above the Fermi level which is localized at the molecule center, in good agreement with tight-binding model calculations of flat bands characteristic for kagome lattices.
