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Optimization of Crystal Growth for Neutron Macromolecular Crystallography
Published on: March 13, 2021
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Optimal Feedback Controlled Assembly of Perfect Crystals.
Xun Tang1, Bradley Rupp2, Yuguang Yang2
1School of Chemical & Biomolecular Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
ACS Nano
|July 9, 2016
Summary
Researchers developed a method for rapid, perfect crystal assembly using controlled electric fields. This closed-loop system navigates kinetic barriers, overcoming limitations of traditional slow or defective crystallization processes.
Area of Science:
- Materials Science
- Chemical Engineering
- Physics
Background:
- Achieving perfectly ordered structures (global free energy minimum) is challenging in systems from molecules to microscale.
- Near-equilibrium assembly is too slow, while faster out-of-equilibrium methods often yield defective structures.
Purpose of the Study:
- To demonstrate rapid and robust assembly of perfect crystals.
- To overcome kinetic bottlenecks in crystallization processes.
- To develop a generalizable method for controlling self-assembly.
Main Methods:
- Utilized closed-loop control of electric field-mediated crystallization of colloidal particles.
- Employed dynamic programming to compute an optimal control policy based on a reaction coordinate dynamic model.
- Implemented real-time tracking of particle configurations and feedback-controlled adjustments of electric fields.
Main Results:
- Successfully guided the assembly of single-domain crystals from polycrystalline states.
- Demonstrated rapid and robust formation of defect-free crystalline structures.
- Showcased the ability to navigate kinetic bottlenecks effectively.
Conclusions:
- The developed closed-loop electric field control enables rapid and perfect crystal assembly.
- This approach offers a generalizable strategy for controlling self-assembly across various scales.
- It provides a pathway to overcome limitations of traditional crystallization methods.
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