title: In vacuo interfacial tetrapyrrole metallation.
abstract: The metallation of tetrapyrroles at well-defined surfaces under ultra-high vacuum conditions represents an unconventional synthesis approach to achieve tetrapyrrole-based metal-organic complexes and architectures. Different protocols, pioneered over the last decade, and now widely applied in several fields, provide an elegant route to metallo-tetrapyrrole systems often elusive to conventional procedures and give access and exquisite insight into on-surface tetrapyrrole chemistry. As highlighted by the functionality of metallo-porphyrins in biological or other environments and by the eminent role of metallo-phthalocyanines in synthetic materials, the control on the metal centres incorporated into the macrocycle is of utmost importance to achieve tailored properties in tetrapyrrole-based nanosystems. In the on-surface scenario, precise metallation pathways were developed, including reactions of tetrapyrroles with metals supplied by physical vapour deposition, chemical vapour deposition or the tip of a scanning tunnelling microscope, and self-metallation by atoms of an underlying support. Herein, we provide a comprehensive overview of in vacuo tetrapyrrole metallation, addressing two-dimensional as well as three-dimensional systems. Furthermore, we comparatively assess the available library of on-surface metallation protocols and elaborate on the state-of-the-art methodology.
authors.affiliation: Physik-Department E20, Technische Universität München (TUM), James-Franck-Str. 1, 85748 Garching, Germany. wau@tum.de and Institute of Condensed Matter Physics (ICMP), École Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland. katharina.diller@epfl.ch.
authors.forename: Katharina
authors.initials: K
authors.lastname: Diller
authors.affiliation: Physik-Department E20, Technische Universität München (TUM), James-Franck-Str. 1, 85748 Garching, Germany. wau@tum.de.
authors.forename: Anthoula C
authors.initials: AC
authors.lastname: Papageorgiou
authors.affiliation: Physik-Department E20, Technische Universität München (TUM), James-Franck-Str. 1, 85748 Garching, Germany. wau@tum.de.
authors.forename: Florian
authors.initials: F
authors.lastname: Klappenberger
authors.affiliation: Physik-Department E20, Technische Universität München (TUM), James-Franck-Str. 1, 85748 Garching, Germany. wau@tum.de.
authors.forename: Francesco
authors.initials: F
authors.lastname: Allegretti
authors.affiliation: Physik-Department E20, Technische Universität München (TUM), James-Franck-Str. 1, 85748 Garching, Germany. wau@tum.de.
authors.forename: Johannes V
authors.initials: JV
authors.lastname: Barth
authors.affiliation: Physik-Department E20, Technische Universität München (TUM), James-Franck-Str. 1, 85748 Garching, Germany. wau@tum.de.
authors.forename: Willi
authors.initials: W
authors.lastname: Auwärter