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Synergetic Spin-Crossover and Luminescence in a Fe(II) Complex with Aggregation-Induced Emission and Twisted
Jinjiang Wu1,2, Qianqian Yang1,2, Jingjing Lu1,2
1State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
Precision Chemistry
|November 28, 2025
Summary
Researchers designed a novel fluorescent ligand, bpp-TPA, and synthesized an iron complex, bpp-TPA-Fe. This complex shows thermally induced spin-state switching coupled with luminescence changes, enabling smart material applications.
Area of Science:
- Coordination Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Spin-state switching is crucial for developing smart materials.
- Designing ligands with tunable properties is key for advanced molecular systems.
Purpose of the Study:
- To synthesize a novel fluorescent ligand (bpp-TPA) and its iron complex (bpp-TPA-Fe).
- To investigate the spin-state switching and luminescent properties of the complex.
- To explore the potential for multifunctional molecular materials.
Main Methods:
- Precise ligand design and synthesis.
- Covalent integration of triphenylamine (TPA) fluorophore and bpp coordination subunit.
- Preparation and characterization of the mononuclear iron complex [Fe-(bpp-TPA)2]·(CF3SO3)2.
- Analysis of spin-state switching and luminescent behavior.
Main Results:
- The synthesized complex bpp-TPA-Fe exhibits reversible thermally induced spin-state switching (T1/2 = 311 K).
- Fluorescent intensity distinctly intensifies upon spin-state conversion, peaking at 360 K.
- The complex displays aggregation-induced emission (AIE) and twisted intramolecular charge transfer (TICT) properties.
- Significant bathochromic shifts observed with increasing solution polarity.
Conclusions:
- A highly precise molecular design strategy yields multifunctional materials with tunable magneto-optical properties.
- The synergistic coupling between spin-state switching and luminescence is demonstrated.
- The developed complex shows promise for next-generation smart material applications.
Keywords:
aggregation-induced emissionluminescencespin-crossoversynergistic effecttwisted intramolecular charge transferMore Related Videos
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