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Published on: February 15, 2016
A general set of order parameters for molecular crystals
Erik E Santiso1, Bernhardt L Trout
1Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
The Journal of Chemical Physics
|February 17, 2011
Summary
This study introduces a novel method for creating order parameters to understand molecular crystallization and polymorph transformations. These parameters, derived from molecular dynamics simulations, aid in studying complex crystal formation processes.
Area of Science:
- Materials Science
- Physical Chemistry
- Chemical Engineering
Background:
- Crystallization is crucial in science and industry (chemical, food, pharmaceutical).
- Designing crystalline materials and processes is complex due to numerous influencing variables.
- A molecular-level understanding of aggregation and organization is needed.
Purpose of the Study:
- To present a new method for constructing order parameters.
- To enable the study of crystallization and polymorph transformations in molecular systems.
- To provide tools for understanding molecular self-assembly into crystal structures.
Main Methods:
- Developing a systematic approach to define order parameters for complex molecular systems.
- Utilizing information from molecular dynamics simulations of crystals.
- Applying the method to study glycine crystallization, benzene crystallization, and terephthalic acid polymorph transformation.
Main Results:
- Successfully constructed order parameters applicable to diverse molecular systems.
- Demonstrated the utility of these parameters in analyzing crystallization and polymorph transitions.
- Provided a framework for systematically defining order parameters from simulation data.
Conclusions:
- The developed order parameters offer a powerful tool for molecular-level studies of crystallization.
- This method facilitates the investigation of complex crystallization phenomena and polymorph control.
- The approach can be extended to study order-disorder transitions in molecular systems.
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