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Updated: Mar 7, 2026
16:24
Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
19.3K
Supramolecular Polymorphism of an Ir(III) Complex: Kinetic/Thermodynamic Control and Mechano-Responsiveness
Yan Chen1,2, Christian Mück-Lichtenfeld3, Qinglong Zhang1
1State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Linggong Road 2, Dalian 116024, China.
Journal of the American Chemical Society
|March 5, 2026
Summary
Researchers achieved control over supramolecular polymorphism in an Ir(III) complex, forming three distinct forms (nanoparticles, nanospheres, nanosheets) by manipulating kinetic and thermodynamic factors. One form
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Crystallography
Background:
- Polymorphism is crucial in pharmaceuticals and materials science, influencing properties.
- Controlling and predicting polymorphs in supramolecular assemblies is challenging.
Purpose of the Study:
- To report the formation of three distinct polymorphs of an Ir(III) complex.
- To investigate the kinetic, thermodynamic, and stimulus-responsive factors governing supramolecular polymorphism.
- To demonstrate the role of polymorphs in supramolecular polymerization and material preparation.
Main Methods:
- Formation of three polymorphs (nanoparticles, nanospheres, nanosheets) of Ir(III) complex 1.
- Denaturation studies and concentration-solvent phase diagrams to determine stability regimes.
- Thermodynamic studies and concentration-temperature phase diagrams for polymorph interconversion.
- Mechano-responsive conversion studies and analysis of thermodynamic parameters.
Main Results:
- Three polymorphs (1A, 1B, 1C) were formed in the same solvent and concentration at room temperature.
- 1A and 1B are kinetic species; 1C is the thermodynamic product.
- Conversion of 1B to 1C is mechano-responsive, requiring mechanical force, not just heating.
- Interconversion between 1B and 1C was achieved by coupling heating/cooling and stirring.
- 1B acts as a delayed intermediate in living supramolecular polymerization and preparation of 2D block heterostructures.
Conclusions:
- Unveiled kinetic, thermodynamic, and stimulus-responsive factors governing supramolecular polymorphism.
- Demonstrated mechano-responsive control over polymorph formation and interconversion.
- Paved the way for designing functional materials with tunable properties through controlled polymorphism.
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