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Updated: May 5, 2026

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Published on: November 9, 2012
How elastically flexible can molecular crystals be? - a new record
Zhengzheng Zhou1,2, Vikram Chandrashekhar Joshi2, Yiwang Guo2
1NMPA Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Hygiene Inspection & Quarantine Science, School of Public Health, Southern Medical University Guangzhou Guangdong 510515 China.
This study reveals that the celecoxib (CEL) molecular crystal demonstrates remarkable elastic flexibility, achieving an elastic strain of at least 8.70%. This finding is crucial for developing advanced functional materials with enhanced mechanical properties.
Area of Science:
- Materials Science
- Crystallography
- Solid-State Chemistry
Background:
- Elastic strain limit is a critical parameter for functional materials.
- The full extent of elastic flexibility in molecular crystals is not well-defined.
Purpose of the Study:
- To investigate and quantify the elastic flexibility of molecular crystals.
- To report a molecular crystal with exceptional elastic properties.
Main Methods:
- Single crystal nanoindentation was used to determine Young's modulus and hardness.
- In-die Heckel analysis was performed on bulk powder to assess plasticity.
Main Results:
- Form I polymorph of celecoxib (CEL) exhibits an elastic strain of at least 8.70%.
- Low Young's modulus (E = 3.18 ± 1.01 GPa) and hardness (H = 39.8 ± 15.6 MPa) were measured.
- High plasticity of the bulk powder was observed.
Conclusions:
- Celecoxib (CEL) represents a molecular crystal with record-high elastic flexibility.
- The findings suggest potential for CEL in applications requiring significant elastic deformation.
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