Journal of the American Chemical Society
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mostly at the zigzag carbon atoms of sublattice A with negligible
1
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1
1
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6
spin density on the atoms of sublattice B.
Notes
The authors declare no competing financial interests.
The principal outcomes of TB analyses are reproduced in our
STS experiments, wherein dI/dV spectroscopy on 1 reveals broad
and pronounced peaks in the DOS centered at -400 mV and +1.15
V (Fig. 2f, also see Fig. S3 for additional STS measurements),
which correspond to the positive and negative ion resonances
ACKNOWLEDGMENT
This work was supported by the Swiss National Science
Foundation (grant numbers 200020-182015 and IZLCZ2-
(
(
PIR and NIR), respectively. Spatial mapping of the dI/dV signal
dI/dV maps) at these bias values (Fig. 2g) exhibits excellent
1
70184), the NCCR MARVEL funded by the Swiss National
Science Foundation (grant number 51NF40-182892), the
European Union’s Horizon 2020 research and innovation program
under grant agreement numbers 696656 and 785219 (Graphene
Flagship Core 2), the Office of Naval Research (grant number
N00014-18-1-2708), ERC Consolidator grant (T2DCP, number
819698), the German Research Foundation (DFG) within the
Cluster of Excellence “Center for Advancing Electronics Dresden
correspondence to the TB-LDOS maps of the SOMOs (-400 mV)
and the singly-unoccupied molecular orbitals (SUMOs, +1.15 V)
of 1. This confirms the assignment of the peaks in the dI/dV
spectrum to molecular orbital resonances, and the associated
Coulomb gap of 1 is deduced to be 1.55 eV. To determine the
magnetic ground state of 1 adsorbed on Au(111), we performed
eigenvalue self-consistent GW calculations including image
charge screening effects from the underlying surface (GW+IC
calculations, see Fig. S4) for the open-shell quartet and doublet
electronic configurations. From these calculations, it is found that
the experimental Coulomb gap of 1.55 eV shows excellent
agreement to the GW+IC frontier orbital gap of 1.67 eV of the
open-shell quartet state of 1, while the GW+IC frontier orbital gap
of 640 meV of the open-shell doublet state differs significantly
from the experimental value. These observations thus strongly
suggest that 1 exhibits an open-shell quartet ground state on
Au(111).
0
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0
(cfaed)” and EnhanceNano (number 391979941), and the
European Social Fund and the Federal State of Saxony (ESF-
Project “GRAPHD”, TU Dresden). Computational support from
the Swiss Supercomputing Center (CSCS) under project ID s904
is gratefully acknowledged.
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ASSOCIATED CONTENT
Supporting Information
The Supporting Information is available free of charge on the
ACS Publications website.
Detailed synthetic description of chemical compounds reported in
this study (Scheme S1-S4) and associated solution
characterization data (Fig. S5-S15), additional STM and STS data
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V. Improved All-Carbon Spintronic Device Design. Sci. Rep.
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AUTHOR INFORMATION
Corresponding Author
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*
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Author Contributions
┴These authors contributed equally.
(15) Bullard, Z.; Costa Girão, E.; Daniels, C.; Sumpter, B. G.; Meunier,
4
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