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Photo-induced chirality switching in a cobaloxime complex crystal
Katsuyoshi Ikeda1, Weitao Liu, Yuen Ron Shen
1Department of Materials Science, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8551, Japan. kikeda@chem.titech.ac.jp
The Journal of Chemical Physics
|April 26, 2005
Summary
Photo-irradiation can switch molecular chirality in cobaloxime crystals. Exciting the cobalt(III) ion
Area of Science:
- Coordination Chemistry
- Photochemistry
- Crystallography
Background:
- Molecular chirality is crucial in various scientific fields.
- Photo-induced transformations offer precise control over molecular properties.
- Cobaloxime complexes are model systems for studying electron transfer and photo-reactivity.
Purpose of the Study:
- To investigate the photo-induced switching of molecular chirality in a cobaloxime complex crystal.
- To compare the effectiveness of different photo-excitation pathways (d-d vs. charge transfer) in inducing chirality changes.
- To elucidate the mechanism and cooperative effects governing chirality switching.
Main Methods:
- Synthesis and characterization of a cobaloxime complex.
- Photo-irradiation experiments using specific wavelengths to excite different electronic transitions.
- Monitoring chirality changes as a function of irradiation time.
- Crystallographic analysis to understand molecular arrangement and interactions.
Main Results:
- Photo-irradiation of the cobaloxime crystal induced switching of molecular chirality.
- Excitation of the cobalt(III) ion's d-d transition was more effective for chirality change than ligand-metal charge transfer.
- Despite being less effective for chirality change, ligand-metal charge transfer excitation initiated the key Co-C bond breaking.
- Chirality change exhibited steplike behavior with irradiation time, indicating cooperative effects.
Conclusions:
- The d-d transition of the cobalt(III) ion plays a critical role in photo-induced chirality switching.
- Chirality switching in the crystal occurs cooperatively, influenced by neighboring molecules.
- Understanding these mechanisms provides insights into light-controlled molecular transformations in solid-state systems.
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