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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Concomitant Polymorphs
1Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Beer Sheva, 84105 (Israel).
Angewandte Chemie (International Ed. in English)
|December 22, 1999
Summary
Concomitant polymorphic crystallization, the simultaneous formation of different crystal structures, is rarely studied. This review explores thermodynamic and kinetic factors influencing this phenomenon, offering insights into crystal energetics.
Area of Science:
- Solid-state chemistry
- Crystallography
- Materials science
Background:
- The simultaneous crystallization of multiple polymorphs is a known but understudied phenomenon.
- Understanding polymorphic behavior is crucial for solid material investigation and crystal energetics.
- Polymorphism impacts material properties and processing.
Purpose of the Study:
- To review the thermodynamic and kinetic factors governing competitive and concomitant polymorphic crystallization.
- To highlight the significance of studying simultaneous polymorph formation.
- To provide examples of concomitant crystallization in various systems.
Main Methods:
- Literature review of thermodynamic and kinetic principles.
- Analysis of case studies on polymorphic crystallization.
- Examination of molecular arrangements in different polymorphs.
Main Results:
- Identified key thermodynamic and kinetic drivers for simultaneous polymorph formation.
- Demonstrated the utility of studying this phenomenon for understanding crystal energetics.
- Presented examples, including a cyanine/oxonol complex, illustrating varied molecular orientations in polymorphs.
Conclusions:
- Systematic study of concomitant polymorphic crystallization offers valuable insights into solid-state behavior.
- Thermodynamic and kinetic factors are critical in controlling which polymorphs form simultaneously.
- Further research into this phenomenon can advance materials science and chemical engineering.
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