Unravelling the Open-Shell Character of Peripentacene on Au(111)

0537007 - ÚFCH JH 2022 RIV US eng J - Journal Article
Sánchez-Grande, A. - Urgel, J. I. - Veis, Libor - Edalatmanesh, Shayan - Santos, J. - Lauwaet, K. - Mutombo, Pingo - Gallego, J. M. - Brabec, Jiří - Beran, Pavel - Nachtigallová, Dana - Miranda, R. - Martín, N. - Jelínek, Pavel - Écija, D.
Unravelling the Open-Shell Character of Peripentacene on Au(111).
Journal of Physical Chemistry Letters. Roč. 12, č. 1 (2021), s. 330-336. ISSN 1948-7185
R&D Projects: GA ČR(CZ) GA18-09914S; GA MŠMT LM2018110; GA ČR(CZ) GJ18-18940Y
Grant - others:AV ČR(CZ) AP1601
Program: Akademická prémie - Praemium Academiae
Institutional support: RVO:61388955 ; RVO:61388963 ; RVO:68378271
Keywords : Au(111) * polycyclic aromatic hydrocarbons * open-shell character
OECD category: Physical chemistry; Physical chemistry (FZU-D); Physical chemistry (UOCHB-X)
Impact factor: 6.888, year: 2021
Method of publishing: Limited access

Polycyclic aromatic hydrocarbons (PAHs) are a family of organic compounds comprising two or more fused aromatic rings which feature manifold applications in modern technology. Among these species, those presenting an open-shell magnetic ground state are of particular interest for organic electronic, spintronic, and non-linear optics and energy storage devices. Within PAHs, special attention has been devoted in recent years to the synthesis and study of the acene and fused acene (periacene) families, steered by their decreasing HOMO–LUMO gap with length and predicted open-shell character above some size. However, an experimental fingerprint of such magnetic ground state has remained elusive. Here, we report on the in-depth electronic characterization of isolated peripentacene molecules on a Au(111) surface. Scanning tunnelling spectroscopy, complemented by computational investigations, reveals an antiferromagnetic singlet ground state, characterized by singlet–triplet inelastic excitations with an experimental effective exchange coupling (Jeff) of 40.5 meV. Our results deepen the fundamental understanding of organic compounds with magnetic ground states, featuring perspectives in carbon-based spintronic devices.
Permanent Link: http://hdl.handle.net/11104/0314769