Diboraperylene Diborinic Acid Self-Assembly on Ag(111)-Kagome Flat Band Localized States Imaged by Scanning Tunneling Microscopy and Spectroscopy
Journal
Angewandte Chemie (International ed. in English)
Date Issued
2024-02-05
Author(s)
Pan, Wun-Chang
Mützel, Carina
Haldar, Soumyajyoti
Hohmann, Hendrik
Heinze, Stefan
Thomale, Ronny
Bode, Matthias
Würthner, Frank
Qi, Jing
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.
Subjects
boron; intermolecular interactions; polycycles; scanning tunneling microscopy and spectroscopy; self-assembly
Type
journal article