Zinc porphyrins wires

In the context of oligo-fluorene (oFL) molecular wires, we will conclude with an outlook that focuses on donor-acceptor conjugates bearing Ceo electron-accepting units and zinc porphyrin (ZnP) or ferrocene (Fc) electron-donating moieties, respectively. Both, the donor and acceptor are covalently connected by oFL bridges of variable length. 

Finally, a DEER study on models for molecular wires made from butadiyne-linked zinc porphyrin oligomers, end-labeled with nitroxide radicals, was performed by Lovett, Anderson, and coworkers [107]. Unlike in [104—106], one can control the conformations of these metalloporphyrin-based strucmres by self-assembly with multidentate amine ligands, which bend the rigid oligomeric structure. The experimentally found end-to-end distances in these complexes match the predictions from molecular dynamics calculations. This study thus presents a proof-of-principle that DEER spectroscopy is also well suited for understanding more complex supramolecular stmctures. 

Fig. 25). Alternatively, one can "reverse the process. Porphyrin array formation can start with imidazolyl zinc porphyrin, which can be immobilized using, for example, thiolate attachment on the electrode surface [90,91]. In this case the porphyrin attached to the electrode can serve as a molecular solder connecting the electrode to polymers made of hundreds of meso-meso-or bis(acetylene)-linked bis(imidazolyl zinc porphyrins) 55 [92]. Molecular wires or light-energy conversion systems could be built on the basis of such technologies. 

Very elegant approach was demonstrated recently when zinc -tetra(4-pyridyl) porphyrin molecules were assembled together with fullerene derivatives into hydrid nanorods. These nanorods demonstrate coaxial cable architecture with the central fullerene-composed n-type wire surrounded by the p-type porphyrin cladding (Figure 33). ... 

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