RT Journal Article
T1 On‐Surface Synthesis and Characterization of a High‐Spin Aza‐[5]‐Triangulene
A1 Vilas‐Varela, Manuel
A1 Romero‐Lara, Francisco
A1 Vegliante, Alessio
A1 Calupitan, Jan Patrick
A1 Martínez, Adrián
A1 Martínez, Adrián
A1 Uriarte‐Amiano, Unai
A1 Friedrich, Niklas
A1 Wang, Dongfei
A1 Schulz, Fabian
A1 Koval, Natalia E.
A1 Sandoval‐Salinas, María E.
A1 Casanova, David
A1 Corso, Martina
A1 Artacho, Emilio
A1 Peña Gil, Diego
A1 Pascual, José Ignacio
K1 Bond-Resolved STM
K1 Magnetic Properties
K1 Surface Chemistry
K1 Triangulene
K1 On-Surface Synthesis
AB Triangulenes are a class of open-shell triangular graphene flakes with total spin increasing with their size. In the last years, on-surface-synthesis strategies have permitted fabricating and engineering triangulenes of various sizes and structures with atomic precision. However, direct proof of the increasing total spin with their size remains elusive. In this work, we report the combined in-solution and on-surface synthesis of a large nitrogen-doped triangulene (aza-[5]-triangulene) on a Au(111) surface, and the detection of its high-spin ground state. Bond-resolved scanning tunneling microscopy images uncovered radical states distributed along the zigzag edges, which were detected as weak zero-bias resonances in scanning tunneling spectra. These spectral features reveal the partial Kondo screening of a high-spin state. Through a combination of several simulation tools, we find that the observed distribution of radical states is explained by a quintet ground state (S=2), instead of the quartet state (S=3/2) expected for the neutral species. This confirms that electron transfer to the metal substrate raises the spin of the ground state. We further provide a qualitative description of the change of (anti)aromaticity introduced by N-substitution, and its role in the charge stabilization on a surface, resulting in an S=2 aza-triangulene on Au(111)
PB Wiley
SN 1433-7851
YR 2023
FD 2023-08-21
LK http://hdl.handle.net/10347/31169
UL http://hdl.handle.net/10347/31169
LA eng
NO Angew. Chem. Int. Ed. 2023, 62, e202307884
NO The authors gratefully acknowledge financial support from MCIN/AEI/10.13039/501100011033 through grants No. PID2019-107338RB, PID2019-109555GB-I00, PCI2019-111933-2 and TED2021-132388B-C42, FIS2017-83780-P, and CEX2020-001038-M, from the ELKARTEK project BRTA QUANTUM (no. KK-2022/00041), from the European Regional Development Fund, from the European Union (EU) H2020 program through the FET Open project SPRING (grant agreement No. 863098) and ERC Synergy Grant MolDAM (951519), Xunta de Galicia (Centro de Investigación de Galicia accreditation 2019–2022, ED431G 2019/03) and Xunta de Galicia-Gain Oportunius Program. F.R.-L. thanks the Spanish Ministerio de Educación y Formación Profesional through the PhD scholarship No. FPU20/03305. F.S. acknowledges funding by the Spanish Ministerio de Ciencia e Innovación through Ramón y Cajal Fellowship RYC2021-034304-I. M.E.S.-S. acknowledges the funding by the UK Research and Innovation under the UK government's Horizon Europe funding guarantee (grant number EP/X020908/1). We thank Thomas Frederiksen, Sofía Sanz, and Ricardo Ortiz for fruitful discussions
DS Minerva
RD 24 abr 2026