| Abstract
| - Lanthanide(III) bis(porphyrin) sandwich complexes of octaethyltetraazaporphyrin (OETAP) were synthesized andcharacterized by UV−vis, IR, and NMR spectroscopies. Cyclic voltammetry results indicate that these neutralsandwich complexes are very easily reduced. Charge-transfer reactions were performed in solution with Ln(OETAP)2 sandwiches and zirconium(IV) bis(porphyrin) sandwiches. The lanthanide sandwiches partially oxidizethe zirconium sandwiches in solution, and a solvent dependence of the charge-transfer reaction was observed.The solid-state properties of these charge-transfer materials were also studied. Magnetic susceptibility resultssuggest weak intermolecular interactions between the sandwiches. The conductivities of the charge-transfer speciesare greatly improved relative to those of the insulating undoped sandwiches, but the conductivities are in thelower semiconducting region. The low conductivity values are thought to be due to poor intermolecular overlap.
- Charge-transfer materials were formed from neutral bis(porphyrin) sandwiches posessing tailored redox properties. Electron-rich zirconium sandwiches served as the donors, while π-radical lanthanide porphyrin complexes were the electron acceptors. The degree of charge transfer in solution was determined by electronic spectroscopy. The observed results were consistent with those predicted by cyclic voltammetry. Conductivity and magnetic measurements indicated weak intermolecular interactions in these materials despite strong intramolecular interactions between the porphyrin rings.
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