Related Experiment Video
Updated: Jun 16, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Oriented aggregation: formation and transformation of mesocrystal intermediates revealed
Virany M Yuwono1, Nathan D Burrows, Jennifer A Soltis
1Department of Chemistry, 207 Pleasant Street SE, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Researchers directly observed mesocrystals, an intermediate state in oriented aggregation, using cryo-transmission electron microscopy (cryo-TEM). These mesocrystals transform into single crystals while dispersed in solution.
Area of Science:
- Materials Science
- Nanotechnology
- Crystallography
Background:
- Oriented aggregation is a process where nanocrystals self-assemble into single crystals.
- This process is hypothesized to involve a mesocrystal intermediate state.
- Mesocrystals are characterized by parallel crystallographic alignment of spatially separated nanocrystals.
Purpose of the Study:
- To provide the first direct observations of mesocrystals.
- To investigate the formation and transformation of mesocrystals in aqueous suspension.
- To characterize the structure of mesocrystals using high-resolution imaging.
Main Methods:
- Utilizing cryo-transmission electron microscopy (cryo-TEM) for direct imaging of nanoparticles in suspension.
- Analyzing high-resolution cryo-TEM images to determine nanocrystal arrangement and alignment.
- Observing dynamic transformations of mesocrystals in the dispersed state.
Main Results:
- Direct visualization of mesocrystals with size and shape comparable to final oriented aggregates.
- Evidence of mesocrystal formation and subsequent transformation into single crystals within the aqueous suspension.
- Confirmation that mesocrystals consist of spatially separated yet crystallographically aligned nanocrystals.
Conclusions:
- Mesocrystals are directly observable intermediates in oriented aggregation.
- Mesocrystal transformation to single crystals can occur in dispersed states.
- Cryo-TEM is a powerful tool for studying dynamic self-assembly processes at the nanoscale.
More Related Videos
18:45Harvesting and Cryo-cooling Crystals of Membrane Proteins Grown in Lipidic Mesophases for Structure Determination by Macromolecular Crystallography
Published on: September 2, 2012
22:00Crystallizing Membrane Proteins for Structure Determination using Lipidic Mesophases
Published on: November 21, 2010
Related Concept Videos
Crystal Growth: Principles of Crystallization
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent – the...
Recrystallization: Solid–Solution Equilibria
Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Determination of Crystal Structures
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Polymer Classification: Crystallinity
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...