864957-74-4Relevant articles and documents
Electron Transfer around a Molecular Corner
Schmidt, Hauke C.,Larsen, Christopher B.,Wenger, Oliver S.
, p. 6696 - 6700 (2018/03/26)
The distance dependence of electron transfer (ET) is commonly investigated in linear rigid rod-like compounds, but studies of molecular wires with integrated corners imposing 90° angles are very rare. By using spirobifluorene as a key bridging element and by substituting it at different positions, two isomeric series of donor-bridge-acceptor compounds with either nearly linear or angled geometries were obtained. Photoinduced ET in both series is dominated by rapid through-bond hole hopping across oligofluorene bridges over distances of up to 70 ?. Despite considerable conformational flexibility, direct through-space and through-solvent ET is negligible even in the angled series. The independence of the ET rate constant on the total number of fluorene units in the angled series is attributed to a rate-limiting tunneling step through the spirobifluorene corner. This finding is relevant for multidimensional ET systems and grids in which individual molecular wires are interlinked at 90° angles.
