Synthesis and Characterization of π-Extended Triangulene

Mishra S, Beyer D, Eimre K, Liu J, Berger R, Groning O, Pignedoli CA, Muellen K, Fasel R, Feng X, Ruffieux P (2019)

Publication Type: Journal article

Publication year: 2019

Journal

Journal of the American Chemical Society American Chemical Society

Book Volume: 141

Pages Range: 10621-10625

Journal Issue: 27

DOI: 10.1021/jacs.9b05319

Abstract

The electronic and magnetic properties of nanographenes strongly depend on their size, shape and topology. While many nanographenes present a closed-shell electronic structure, certain molecular topologies may lead to an open-shell structure. Triangular-shaped nanographenes with zigzag edges, which exist as neutral radicals, are of considerable interest both in fundamental science and for future technologies aimed at harnessing their intrinsic high-spin magnetic ground states for spin-based operations and information storage. Their synthesis, however, is extremely challenging owing to the presence of unpaired electrons, which confers them with enhanced reactivity. We report a combined in-solution and on-surface synthesis of π-extended triangulene, a non-Kekulé nanographene with the structural formula C33H15, consisting of ten benzene rings fused in a triangular fashion. The distinctive topology of the molecule entails the presence of three unpaired electrons that couple to form a spin quartet ground state. The structure of individual molecules adsorbed on an inert gold surface is confirmed through ultrahigh-resolution scanning tunneling microscopy. The electronic properties are studied via scanning tunneling spectroscopy, wherein unambiguous spectroscopic signatures of the spin-split singly occupied molecular orbitals are found. Detailed insight into its properties is obtained through tight-binding, density functional and many-body perturbation theory calculations, with the latter providing evidence that π-extended triangulene retains its open-shell quartet ground state on the surface. Our work provides unprecedented access to open-shell nanographenes with high-spin ground states, potentially useful in carbon-based spintronics.

Involved external institutions

Eidgenössische Materialprüfungs- und Forschungsanstalt (Empa) / Swiss Federal Laboratories for Materials Science & Technology CH Switzerland (CH) Technische Universität Dresden DE Germany (DE) Max-Planck-Institut für Polymerforschung (MPI-P) / Max Planck Institute for Polymer Research DE Germany (DE)

How to cite

APA:

Mishra, S., Beyer, D., Eimre, K., Liu, J., Berger, R., Groning, O.,... Ruffieux, P. (2019). Synthesis and Characterization of π-Extended Triangulene. Journal of the American Chemical Society, 141(27), 10621-10625. https://doi.org/10.1021/jacs.9b05319

MLA:

Mishra, Shantanu, et al. "Synthesis and Characterization of π-Extended Triangulene." Journal of the American Chemical Society 141.27 (2019): 10621-10625.

BibTeX: Download