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Updated: Aug 16, 2025
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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
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Solid-solid Phase Transitions between Crystalline Polymorphs of Organic Materials
1Laboratoire SMS - UR 3233, Université Rouen Normandie, Mont Saint Aignan, F 76821, France.
Current Pharmaceutical Design
|December 22, 2022
Summary
This review explores solid-solid phase transitions in organic crystalline solids, including active pharmaceutical ingredients (APIs). Predicting these transitions for specific molecules remains challenging despite a general understanding of polymorphism.
Area of Science:
- Solid-state chemistry and materials science, focusing on crystalline organic materials.
Background:
- Polymorphism and solid-solid phase transitions are crucial for organic molecules, including active pharmaceutical ingredients (APIs).
- Understanding these transitions is key to controlling material properties and applications like drug product bioavailability.
Approach:
- This review synthesizes experimental methods for analyzing phase transitions, complemented by computational and theoretical approaches for mechanism visualization.
- It covers thermodynamics, transition mechanisms (displacive and concerted), and experimental techniques.
Key Points:
- Thermodynamics, including Gibbs free energy, temperature, and pressure, governs phase transitions between polymorphs.
- Key transition mechanisms include displacive and concerted processes within organic crystals.
- Applications such as heat storage and controlling drug product bioavailability through metastable phases are discussed.
Conclusions:
- While the general theory of polymorphism is established, predicting phase transition behavior for specific organic molecules remains complex.
- Further research is needed to refine predictive models for solid-state transformations.
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