Multistimuli-Responsive Molecular Photoswitches Based on Bimetallic Ru(II) and Os(II) Terpyridine Complexes
Soumi Das1, Raju Biswas1, Sujoy Baitalik1
1Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India.
Inorganic Chemistry
|August 6, 2025
Summary
Novel luminescent bimetallic complexes of Ruthenium(II) and Osmium(II) exhibit tunable photoswitching. These stimuli-responsive materials show enhanced photoisomerization, making them suitable for advanced photochemical applications.
Area of Science:
- Coordination Chemistry
- Photochemistry
- Materials Science
Background:
- Development of stimuli-responsive luminescent materials is crucial for advanced applications.
- Metal complexes offer tunable photophysical properties and reactivity.
- Designing ligands with specific functional groups is key to achieving desired responses.
Purpose of the Study:
- To synthesize and characterize novel luminescent bimetallic Ruthenium(II) and Osmium(II) complexes.
- To investigate the photoisomerization behavior and stimuli-responsiveness of these complexes.
- To explore their potential in advanced photochemical applications.
Main Methods:
- Synthesis and full characterization of bimetallic complexes using specific bridging and capping ligands.
- Spectroscopic analysis (UV-vis absorption and emission) to determine photophysical properties.
- Investigation of photoisomerization dynamics under various stimuli (anions, light, redox agents).
Main Results:
- Designed complexes exhibit intense UV-vis absorption and visible-to-NIR emission.
- Enhanced acidity of -CH2 protons allows for anion-responsive luminescence.
- Efficient and tunable photoisomerization (trans-trans to trans-cis and vice versa) triggered by light and other stimuli.
- Significant enhancement in photoisomerization rate and quantum yield observed under specific conditions.
Conclusions:
- The synthesized bimetallic complexes demonstrate multistimuli-responsive behavior.
- Tunable photoswitching capabilities combined with enhanced photoisomerization efficiency are achieved.
- These complexes hold promise for advanced photochemical applications requiring precise control over light-induced processes.
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