TY  - JOUR
AU  - Haags, Anja
AU  - Reichmann, Alexander
AU  - Fan, Qitang
AU  - Egger, Larissa
AU  - Kirschner, Hans
AU  - Naumann, Tim
AU  - Werner, Simon
AU  - Vollgraff, Tobias
AU  - Sundermeyer, Jörg
AU  - Eschmann, Lukas
AU  - Yang, Xiaosheng
AU  - Brandstetter, Dominik
AU  - Posseik, Francois
AU  - Koller, Georg
AU  - Gottwald, Alexander
AU  - Richter, Mathias
AU  - Ramsey, Michael G.
AU  - Rohlfing, Michael
AU  - Puschnig, Peter
AU  - Gottfried, J. Michael
AU  - Soubatch, Serguei
AU  - Tautz, F. Stefan
TI  - Kekulene: On-Surface Synthesis, Orbital Structure, and Aromatic Stabilization
JO  - ACS nano
VL  - 14
IS  - 11
SN  - 1936-086X
CY  - Washington, DC
PB  - Soc.
M1  - FZJ-2021-03370
SP  - 15766 - 15775
PY  - 2020
AB  - We revisit the question of kekulene’s aromaticity by focusing on the electronic structure of its frontier orbitals as determined by angle-resolved photoemission spectroscopy. To this end, we have developed a specially designed precursor, 1,4,7(2,7)-triphenanthrenacyclononaphane-2,5,8-triene, which allows us to prepare sufficient quantities of kekulene of high purity directly on a Cu(111) surface, as confirmed by scanning tunneling microscopy. Supported by density functional calculations, we determine the orbital structure of kekulene’s highest occupied molecular orbital by photoemission tomography. In agreement with a recent aromaticity assessment of kekulene based solely on C–C bond lengths, we conclude that the π-conjugation of kekulene is better described by the Clar model rather than a superaromatic model. Thus, by exploiting the capabilities of photoemission tomography, we shed light on the question which consequences aromaticity holds for the frontier electronic structure of a π-conjugated molecule.
LB  - PUB:(DE-HGF)16
C6  - 33186031
UR  - <Go to ISI:>//WOS:000595533800118
DO  - DOI:10.1021/acsnano.0c06798
UR  - https://juser.fz-juelich.de/record/894718
ER  -