Nanographenes (NGs) and graphene nanoribbons (GNRs) are molecular-level bridges to bulk-carbon materials. When synthesized with atomic precision via, for example, bottom-up strategies, a direct connection between the structure and properties is demonstrable. This is of key interest, especially considering practical applications. In the current work, we report the synthesis and comprehensive photophysical characterization of a full-benzenoid nanographene (NG-Br) and its covalent conjugate featuring a porphyrin (NG-(Zn)Por). Our synthetic approach relies on a cascade of Suzuki coupling, reduction, and Sandmeyer bromination reactions, starting from halogenated nitrobenzene derivatives. Knowing at which concentration aggregation occurs is important to study either monomers of NG-Br or its aggregates. In organic solvents, the association constant of NG-Br exceeds 1 × 106 M–1. Photophysical and theoretical analyses on the monomer revealed a subtle energy proximity between (S1)/(Lb) and (S2)/(La) that is the basis for strong vibronic coupling via the Herzberg–Teller mechanism, as well as (S1,1) and (S2,0) vibronic mixing. In NG-(Zn)Por, an ultrafast (S1–S1) energy transfer from NG to the porphyrin was observed. Our findings are essential for establishing an unambiguous structure–property relationship for NGs and 9-armchair GNRs, providing a blueprint for their use in optoelectronic devices ranging from single-electron transistors to OLEDs and organic solar cells.

Before 1985, it was generally accepted that elemental carbon exists in two forms, or allotropes: diamond and graphite. Then, Kroto et al. identified the signature of a new, stable form of carbon that ...

[5]Helicene-bridged dimeric N-heterotriangulenes were synthesized. Their successive oxidation allowed the study of the electronic coupling between the nitrogen centers. The radical cation with its st....

Momentan verbrennen wir noch große Mengen fossiler Energieträger wie Erdöl oder Kohle, um unseren Energiehunger zu stillen. Dabei entsteht das Treibhausgas Kohlendioxid, das in der Atmosphäre wie eine...

The 32nd International Conference on Photochemistry will take place from July 13 (Sunday) to July 18 (Friday), 2025 in Aachen (Germany). The event is jointly organized by the RWTH Aachen University…

A multilayer-stacked two-dimensional polyaniline crystal shows high electrical conductivity and unique out-of-plane metallic transport behaviour, indicating potential for strong electronic coupling beyond in-plane interactions and three-dimensional metallic conductivity.

Molecular approaches in quantum information science are highly promising, but the synthesis and scale-up of suitable covalently linked moieties represent major challenges. Here it is demonstrated that...

Halide permeation through a single benzene-sized defect in a molecular nanographene shows the permeability of fluoride, chloride and bromide, whereas iodide is impermeable.

Stoddart received the 2016 Nobel Prize in Chemistry for work on molecular machines