Comparing Spin‐Selective Charge Transport through Donor–Bridge–Acceptor Molecules with Different Oligomeric Aromatic Bridges

Abstract

Burning bridges: The exponential distance dependence (β value) of singlet and triplet charge recombination (CR) pathways is determined for three donor-bridge-acceptor (DBA) molecules. p-Phenylethynylene and fluorenone bridges have similar β values, which differ significantly from those of p-phenylene bridges, thus implying that β for both singlet and triplet CR is system-dependent, not bridge-specific.

Assessing electron transfer reactions and catalysis in multicopper oxidases with operando X-ray absorption spectroscopy

“…Usually, an internal electron transfer reaction using multi-step pathways is preferred to promote fast and efficient reactions even for long distance transfer mechanisms between the donor and the final electron acceptor. In this case, an electronic bridge can play an important role to minimize the time as well as the energy required to promote such a reaction, represented as a donor-bridge-acceptor (D-B-A) system 21,22 . Thus, acting more than an electronic shell that helps with the docking and reduction of O 2 , the catalytic center with the four Cu ions have to get reduced to the + 1 oxidation state to promote the effective electron transfer between the organic substrate (or electrode) and the molecular oxygen, behaving as a redox active bridge in a D-B-A system 23 .…”

Three Redox States of a Diradical Acceptor–Donor–Acceptor Triad: Gating the Magnetic Coupling and the Electron Delocalization

“…Challenging are dyadic systems formed by donor (D) and acceptor (A) units connected by conjugated bridges due to their potential applications as molecular wires or switches. [1][2][3][4][5][6][7][8] Organic mixed-valence (MV) compounds containing at least two redox sites with two different oxidation states connected through a conjugated bridge are good examples for this kind of compounds. [9][10][11][12][13][14] On the other hand, research on organic molecules containing several stable radical centres linked through ferromagnetic coupling bridges have also received much attention during the past decades.…”

Oligo(p‐phenyleneethynylene) (OPE) Molecular Wires: Synthesis and Length Dependence of Photoinduced Charge Transfer in OPEs with Triarylamine and Diaryloxadiazole End Groups

“…[18] UV-Visible absorption studies on OPE wires terminated with dialkylamino donor and cyano, formyl or nitro acceptor groups showed a competition between the extension of the chromophores and a decrease of the ICT upon increasing the number of PE repeat units. [19] More extensive photophysical studies on series of extended-TTF-OPE-pyrrolidinoC 60 , [20,21] porphyrin-OPE-pyrrolidinoC 60 [22] and 3,5-dimethyl-4-(9-anthracenyl)julolidine-OPEnaphthalene-bis(dicarboximide) systems [23] gave  values of 0.20, 0.11 and 0.23 Å -1 , respectively. Other examples include boron dipyrromethene (BODIPY)-OPE systems.…”

“…[21,23,38] The experimental data can be readily fitted to equation 1 giving an attenuation factor of = 0. [22] and = 0.20 Å -1 for extended-TTF-OPE-pyrrolidinoC 60 .…”