On-Surface Synthesis and Characterization of Super-nonazethrene

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Elia Turco - , Swiss Federal Laboratories for Materials Science and Technology (Empa) (Author)
  • Shantanu Mishra - , Swiss Federal Laboratories for Materials Science and Technology (Empa) (Author)
  • Jason Melidonie - , Chair of Molecular Functional Materials (cfaed) (Author)
  • Kristjan Eimre - , Swiss Federal Laboratories for Materials Science and Technology (Empa) (Author)
  • Sebastian Obermann - , Chair of Molecular Functional Materials (cfaed) (Author)
  • Carlo A. Pignedoli - , Swiss Federal Laboratories for Materials Science and Technology (Empa) (Author)
  • Roman Fasel - , Swiss Federal Laboratories for Materials Science and Technology (Empa), University of Bern (Author)
  • Xinliang Feng - , Chair of Molecular Functional Materials (cfaed), Max Planck Institute of Microstructure Physics (Author)
  • Pascal Ruffieux - , Swiss Federal Laboratories for Materials Science and Technology (Empa) (Author)

Abstract

Beginning with the early work of Clar et al. in 1955, zethrenes and their laterally extended homologues, super-zethrenes, have been intensively studied in the solution phase and widely investigated as optical and charge transport materials. Superzethrenes are also considered to exhibit an open-shell ground state and may thus serve as model compounds to investigate nanoscale π-magnetism. However, their synthesis is extremely challenging due to their high reactivity. We report here the on-surface synthesis of the hitherto largest zethrene homologue - super-nonazethrene - on Au(111). Using single-molecule scanning tunneling microscopy and spectroscopy, we show that super-nonazethrene exhibits an open-shell singlet ground state featuring a large spin polarization-driven electronic gap of 1 eV. Consistent with the emergence of an open-shell ground state, high-resolution tunneling spectroscopy reveals singlet-triplet spin excitations in super-nonazethrene, characterized by a strong intramolecular magnetic exchange coupling of 51 meV. Given the paucity of zethrene chemistry on surfaces, our results therefore provide unprecedented access to large, open-shell zethrene compounds amenable to scanning probe measurements, with potential application in molecular spintronics.

Details

Original languageEnglish
Pages (from-to)8314-8319
Number of pages6
JournalJournal of Physical Chemistry Letters
Volume12
Issue number34
Publication statusPublished - 2 Sept 2021
Peer-reviewedYes

External IDs

PubMed 34428064