Neutral organic radical formation by chemisorption on metal surfaces
Ajayakumar, M. R. (Institut de Ciència de Materials de Barcelona)
Moreno, Cesar (Institut Català de Nanociència i Nanotecnologia)
Alcón, Isaac (Universitat de Barcelona. Departament de Ciència de Materials i Química Física)
Illas, Francesc (Universitat de Barcelona. Departament de Ciència de Materials i Química Física)
Rovira Angulo, Concepció (Institut de Ciència de Materials de Barcelona)
Veciana i Miró, Jaume (Institut de Ciència de Materials de Barcelona)
Bromley, Stefan (Universitat de Barcelona. Departament de Ciència de Materials i Química Física)
Mugarza, Aitor (Institut Català de Nanociència i Nanotecnologia)
Mas-Torrent, Marta (Institut de Ciència de Materials de Barcelona)

Date:	2020
Abstract:	Organic radical monolayers (r-MLs) bonded to metal surfaces are potential materials for the development of molecular (spin)electronics. Typically, stable radicals bearing surface anchoring groups are used to generate r-MLs. Following a recent theoretical proposal based on a model system, we report the first experimental realization of a metal surface-induced r-ML, where a rationally chosen closed-shell precursor 3,5-dichloro-4-[bis(2,4,6-trichlorophenyl)methylen]cyclohexa-2,5-dien-1-one (1) transforms into a stable neutral open-shell species () via chemisorption on the Ag(111) surface. X-ray photoelectron spectroscopy reveals that the >C=O group of 1 reacts with the surface, forming a C-O-Ag linkage that induces an electronic rearrangement that transforms 1 to . We further show that surface reactivity is an important factor in this process whereby Au(111) is inert towards 1, whereas the Cu(111) surface leads to dehalogenation reactions. The radical nature of the Ag(111)-bound monolayer was further confirmed by angle-resolved photoelectron spectroscopy and electronic structure calculations, which provide evidence of the emergence of the singly occupied molecular orbital (SOMO) of 1.
Grants:	European Commission 600385 European Commission 306826 Ministerio de Economía y Competitividad RTI2018-095460-B-I00 Ministerio de Economía y Competitividad MDM-2017-0767 Ministerio de Economía y Competitividad SEV-2017-0706 Ministerio de Economía y Competitividad CTQ2016-80030-R Ministerio de Economía y Competitividad MAT2016-78293-C6-2-R Ministerio de Economía y Competitividad SEV-2015-0496 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-13 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-918
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	Angle resolved photoelectron spectroscopy ; Bearing surfaces ; Electronic structure calculations ; Experimental realizations ; Organic radicals ; Potential materials ; Singly occupied molecular orbitals ; Surface reactivity
Published in:	Journal of physical chemistry letters, Vol. 11, issue 10 (May 2020) , p. 3897-3904, ISSN 1948-7185

DOI: 10.1021/acs.jpclett.0c00269

Post-print 27 p, 1.3 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles