Effects of ring tilting on rates of intramolecular electron transfer in mixed-valence 1',2',1''',2'''-tetraethyl-, 1',3',1''',3'''-tetraethyl-, and 1',2',4',1''',2''',4'''-hexaethylbiferrocenium triiodides

Long-distance electronic interaction in a molecular wire consisting of a ferrocenyl–ethynyl unit bridging two [(η5-C5H5)(dppe)M] metal centers

“…The two least-squares-fitting Cp planes in a given ferrocenyl moiety are nearly parallel, and the dihedral angle is 0.86(8)°. Inspection of the average distances of Fe-C (2.048(3) Å) and Fe-Cp (1.6549(2) Å) indicates that the metallocenes are in Fe 2+ oxidation state [30,31]. The bond distances and angles about the Cp rings vary little and they are close to those reported for analogous ferrocenes.…”

Synthesis, electrochemistry, and photophysical properties of binuclear ruthenium(II)–terpyridine complexes comprising redox-active ferrocenyl spacer

“…Excited-states of ½Ru III a -tpy À -fc II -fc III -tpy-Ru II b and ½Ru III a -tpy À -fc III -fc IItpy-Ru II b are energetically degenerated, resulting form the rapid electron-transfer process between two Fe 2+ and Fe 3+ centers. In our earlier reports [23], the rate of intramolecular electron-transfer in mixed-valence biferrocenium cations in solution state was estimated to be >$10 12 s À1 (s: <1 ps). The presence of lower energy ferrocenium-centered ½Ru II a -tpy À -fc III -fc III -tpy-Ru II b state provides an additional channel for excited-states decay.…”

“…The polyferrocenyl spacers themselves are insulators, but can be converted into semiconducting materials by selective oxidation of ferrocenyl units to form mixed-valence polyferrocenium spacers. In our earlier reports, a rapid intramolecular electron-transfer process in mixed-valence biferrocenium was observed [23]. Thus, mixed-valence polyferrocenium spacers, which possibly give an effective p-delocalization along main chain, can serve as model systems for molecular wires.…”

Exploiting Conformational Dynamics of Structurally Tuned Aryl-Substituted Terpyridyl Ruthenium(II) Complexes to Inhibit Charge Recombination in Dye-Sensitized Solar Cells

“…In other words, these systems are exhibiting properties of a rectifier or an “electron turnstile” . The effect orginates in modifications to the electronic coupling for both ET events (forward and backward) and is related to work where controlled torsions between aryl-subunits in an ET pathway influence ET and triplet energy-tranfer rates. − Scheme , while idealized, is presented to help summarize the application of these original DBA ideas in the context of DSSCs, using the kinds of dye systems explored herein (vide infra). Step 1 shows a vertical (Franck–Condon) preparation of an MLCT state.…”