Photoinduced Electron Transfer Processes in Rotaxanes Containing [60]Fullerene and Ferrocene: Effect of Axle Charge on Light-Induced Molecular Motion

Atula S. D. Sandanayaka; Hisahiro Sasabe; Yasuyuki Araki; Nobuhiro Kihara; Yoshio Furusho; Toshikazu Takata; Osamu Ito

doi:10.1071/CH05311

RESEARCH FRONT

Photoinduced Electron Transfer Processes in Rotaxanes Containing [60]Fullerene and Ferrocene: Effect of Axle Charge on Light-Induced Molecular Motion

Atula S. D. Sandanayaka ^A , Hisahiro Sasabe ^B , Yasuyuki Araki ^A , Nobuhiro Kihara ^B , Yoshio Furusho ^C , Toshikazu Takata ^D ^E and Osamu Ito ^A ^E

+ Author Affiliations

- Author Affiliations

^A Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 Japan.

^B Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, Osaka 599-8531, Japan.

^C Yashima Super-Structured Helix Project, Japan Science and Technology Agency, Nagoya 552-8555, Japan.

^D Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Tokyo 152-8552, Japan.

^E Corresponding authors. Email: ttakata@polymer.titech.ac.jp; ito@tagen.tohoku.ac.jp

Australian Journal of Chemistry 59(3) 186-192 https://doi.org/10.1071/CH05311
Submitted: 16 November 2005 Accepted: 18 January 2006 Published: 24 March 2006

Abstract

Two rotaxanes containing [60]fullerene (C₆₀) as pendants on a crown-ether necklace, to which ferrocene (Fc) as axle stoppers were added, have been synthesized. One rotaxane has an ammonium cation in the centre of the axle (C₆₀;Fc)_Rot+ and the other has a neutral axle (C₆₀;Fc)_Rot. Optimized structures, calculated using a molecular orbital method, suggest that in the ground states (C₆₀;Fc)_Rot+ has a shorter distance between C₆₀ and Fc than that of (C₆₀;Fc)_Rot. In both rotaxanes, efficient intra-rotaxane photoinduced electron-transfer processes have been observed by the selective excitation of C₆₀ which acts as a photosensitized electron acceptor. The rates and efficiencies of the charge-separation and charge-recombination processes were evaluated by time-resolved fluorescence and transient absorption measurements with changing solvent polarity. From the different kinetic parameters between (C₆₀;Fc)_Rot+ and (C₆₀;Fc)_Rot, the light-induced molecular motions of these rotaxanes in the excited states and charge-separated states were separately revealed.

Acknowledgments

This present work was supported by a Grants-in-Aid on Scientific Research on Priority Areas (417) from the Ministry of Education, Culture, Sports, Science and Technology of Japan.

References

Photoinduced Electron Transfer Processes in Rotaxanes Containing [60]Fullerene and Ferrocene: Effect of Axle Charge on Light-Induced Molecular Motion

Abstract

Acknowledgments

Subscriber Login