% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@ARTICLE{Haags:1046002,
      author       = {Haags, Anja and Reichmann, Alexander and Ruan, Zilin and
                      Fan, Qitang and Egger, Larissa and Kirschner, Hans and
                      Naumann, Tim and Werner, Simon and Kleykamp, Olaf and
                      Martinez-Castro, Jose and Lüpke, Felix and Bocquet,
                      François C. and Kumpf, Christian and Soubatch, Serguei and
                      Gottwald, Alexander and Koller, Georg and Ramsey, Michael G.
                      and Richter, Mathias and Sundermeyer, Jörg and Puschnig,
                      Peter and Gottfried, J. Michael and Tautz, F. Stefan and
                      Wenzel, Sabine},
      title        = {{M}ulti-{O}rbital {C}harge {T}ransfer into {N}onplanar
                      {C}ycloarenes {R}evealed with {CO}-{F}unctionalized {T}ips},
      publisher    = {arXiv},
      reportid     = {FZJ-2025-03649},
      year         = {2025},
      abstract     = {On-surface synthesis has allowed for the tuneable
                      preparation of numerous molecular systems with variable
                      properties. Recently, we demonstrated the highly selective
                      synthesis of kekulene $(>99\%)$ on Cu(111) and isokekulene
                      $(92\%)$ on Cu(110) from the same molecular precursor (Ruan
                      et al., Angew. Chem. Int. Ed. 2025, e202509932). Scanning
                      tunneling microscopy with CO-functionalized tips can
                      identify the single molecules on the basis of their
                      geometric structure at a low coverage on Cu(110), but it
                      also detects complex features due to electronic
                      contributions close to the Fermi energy. Here, we
                      investigate the origin of these features by simulating STM
                      images based on a weighted sum of multiple molecular
                      orbitals, for which we employ weights based on the
                      calculated molecular-orbital projected density of states.
                      This allows for an experimental confirmation of charge
                      transfer from the surface into multiple formerly unoccupied
                      molecular orbitals for single molecules of kekulene as well
                      as isokekulene in its two nonplanar adsorption
                      configurations. In comparison, the area-integrating
                      photoemission orbital tomography technique confirms the
                      charge transfer as well as the high selectivity for the
                      formation of a full monolayer of mainly isokekulene on
                      Cu(110). Our STM-based approach is applicable to a wide
                      range of adsorbed molecular systems and specifically also
                      suited for strongly interacting surfaces, nonplanar
                      molecules, and such molecules which can only be prepared at
                      extremely low yields.},
      keywords     = {Chemical Physics (physics.chem-ph) (Other) / Materials
                      Science (cond-mat.mtrl-sci) (Other) / FOS: Physical sciences
                      (Other)},
      cin          = {PGI-3},
      cid          = {I:(DE-Juel1)PGI-3-20110106},
      pnm          = {5213 - Quantum Nanoscience (POF4-521) / SFB 1083 A12 -
                      Struktur und Anregungen von hetero-epitaktischen
                      Schichtsystemen aus schwach wechselwirkenden 2D-Materialien
                      und molekularen Schichten (A12) (385975694) / TACY -
                      Tackling the Cyclacene Challenge (101071420) / DFG project
                      G:(GEPRIS)511561801 - Manipulierung von 2D Supraleitung und
                      Majorana Zuständen auf der Nanoskala (511561801) / ML4Q -
                      Machine Learning for Quantum (101120240)},
      pid          = {G:(DE-HGF)POF4-5213 / G:(GEPRIS)385975694 /
                      G:(EU-Grant)101071420 / G:(GEPRIS)511561801 /
                      G:(EU-Grant)101120240},
      typ          = {PUB:(DE-HGF)25},
      doi          = {10.48550/ARXIV.2509.00736},
      url          = {https://juser.fz-juelich.de/record/1046002},
}