Intrachain Electron Transfer in Conducting Oligomers and Polymers: The Mixed Valence Approach
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- 作者：Jean Christophe Lacroix ; Kathleen Isabelle Chane-Ching ; Fabrice Maquè ; re ; and Franç ; ois Maurel
- 刊名：Journal of the American Chemical Society
- 出版年：2006
- 出版时间：June 7, 2006
- 年：2006
- 卷：128
- 期：22
- 页码：7264 - 7276
- 全文大小：280K
- 年卷期：v.128,no.22(June 7, 2006)
- ISSN：1520-5126
文摘
Organic mixed valence compounds consisting of bisdiarylamino charge-bearing units with anoligothiophene bridge and oligothiophene radical cations have been compared using molecular modeling.The study has been performed with oligomers of 1 to 22 thiophene units. These two series of moleculeshave several properties in common, and intramolecular Single Electron Transfer (SET) in both series canbe described within the same theoretical framework. Conducting oligomer radical cations and slightly dopedconducting polymers appear as special cases of the vast ensemble of organic mixed valence compounds.Short oligomers are class III, whereas longer oligomers and conducting polymers are class II. Therefore,doped conducting polymers cannot be correctly modeled using oligomers with a short conjugation length.Experimental evidence extracted from the literature confirms these findings. Single electron transfer theoriescan thus be used when studying interchain and intrachain electron transfer in slightly doped conductingpolymers and in materials consisting of short oligomers. This makes it possible to extract from the UV-vis-near-IR spectra the electron-transfer constant rate along or between the 
-conjugated chain. The maindifferences among inorganic, organic, and conducting oligomer or polymer mixed valence compounds liesin the Hab and 
values associated with these different series. Inorganic mixed valence compounds havesmall Hab and values; organic mixed valence compounds have large Hab and values, whereas conductingoligomers and polymers have large Hab but small values. This induces charge delocalization to occur forsystems larger than those of inorganic and nitrogen-centered organic mixed valence compounds.
-conjugated chain. The maindifferences among inorganic, organic, and conducting oligomer or polymer mixed valence compounds liesin the Hab and values associated with these different series. Inorganic mixed valence compounds havesmall Hab and values; organic mixed valence compounds have large Hab and values, whereas conductingoligomers and polymers have large Hab but small values. This induces charge delocalization to occur forsystems larger than those of inorganic and nitrogen-centered organic mixed valence compounds.