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arXiv · 2110.11449

Disentangling the Complex Electronic Structure of an Adsorbed Nanographene: Cycloarene C108

Jose Martinez-Castro·Rustem Bolat·Qitang Fan·Simon Werner·Hadi H. Arefi·Taner Esat·Jörg Sundermeyer·Christian Wagner·J. Michael Gottfried·Ruslan Temirov·Markus Ternes·F. Stefan Tautz
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Abstract

We combine low-temperature scanning tunneling spectroscopy, CO functionalized tips and algorithmic data analysis to investigate the electronic structure of the molecular cycloarene C108 (graphene nanoring) adsorbed on a Au(111) surface. We demonstrate that CO functionalized tips enhance the visibility of molecular resonances, both in differential conductance spectra and in real-space topographic images without introducing spurious artifacts. Comparing our experimental data with ab-initio density functional theory reveals a remarkably precise agreement of the molecular orbitals and enables us to disentangle close-lying molecular states only separated by 50 meV at an energy of 2 eV below the Fermi level. We propose this combination of techniques as a promising new route for a precise characterization of complex molecules and other physical entities which have electronic resonances in the tip-sample junction.

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Jose Martinez-Castro, Rustem Bolat, Qitang Fan, Simon Werner, Hadi H. Arefi, Taner Esat, Jörg Sundermeyer, Christian Wagner, J. Michael Gottfried, Ruslan Temirov, Markus Ternes, F. Stefan Tautz. 2021-10-21. Disentangling the Complex Electronic Structure of an Adsorbed Nanographene: Cycloarene C108. https://doi.org/10.1038/s43246-022-00275-x

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