Phase behavior and design rules for plastic colloidal crystals of hard polyhedra via consideration of directional entropic forces

We show how directional entropic forces (which are set by particle shape) give rise to distinct behaviors in entropic systems with translational order and orientational disorder.

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Hydrodynamic and frictional modulation of deformations in switchable colloidal crystallites

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1921805117 ◽

2020 ◽

Vol 117 (23) ◽

pp. 12700-12706

Author(s):

Young Ki Lee ◽

Xiaoguai Li ◽

Paris Perdikaris ◽

John C. Crocker ◽

Celia Reina ◽

...

Keyword(s):

Principal Component Analysis ◽

Diffusion Coefficients ◽

Particle Shape ◽

Colloidal Crystals ◽

Principal Component ◽

Nucleation And Growth ◽

Spherically Symmetric ◽

Dynamical Models ◽

Micrometer Scale ◽

The Impact

Displacive transformations in colloidal crystals may offer a pathway for increasing the diversity of accessible configurations without the need to engineer particle shape or interaction complexity. To date, binary crystals composed of spherically symmetric particles at specific size ratios have been formed that exhibit floppiness and facile routes for transformation into more rigid structures that are otherwise not accessible by direct nucleation and growth. There is evidence that such transformations, at least at the micrometer scale, are kinetically influenced by concomitant solvent motion that effectively induces hydrodynamic correlations between particles. Here, we study quantitatively the impact of such interactions on the transformation of binary bcc-CsCl analog crystals into close-packed configurations. We first employ principal-component analysis to stratify the explorations of a bcc-CsCl crystallite into orthogonal directions according to displacement. We then compute diffusion coefficients along the different directions using several dynamical models and find that hydrodynamic correlations, depending on their range, can either enhance or dampen collective particle motions. These two distinct effects work synergistically to bias crystallite deformations toward a subset of the available outcomes.

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Particle analogs of electrons in colloidal crystals

Science ◽

10.1126/science.aaw8237 ◽

2019 ◽

Vol 364 (6446) ◽

pp. 1174-1178 ◽

Cited By ~ 29

Author(s):

Martin Girard ◽

Shunzhi Wang ◽

Jingshan S. Du ◽

Anindita Das ◽

Ziyin Huang ◽

...

Keyword(s):

Colloidal Crystal ◽

Colloidal Crystals ◽

Insulator Transition ◽

Metal Insulator Transition ◽

Design Rules ◽

Metal Insulator ◽

Grafting Density ◽

And Diffusion ◽

Classical Picture

A versatile method for the design of colloidal crystals involves the use of DNA as a particle-directing ligand. With such systems, DNA-nanoparticle conjugates are considered programmable atom equivalents (PAEs), and design rules have been devised to engineer crystallization outcomes. This work shows that when reduced in size and DNA grafting density, PAEs behave as electron equivalents (EEs), roaming through and stabilizing the lattices defined by larger PAEs, as electrons do in metals in the classical picture. This discovery defines a new property of colloidal crystals—metallicity—that is characterized by the extent of EE delocalization and diffusion. As the number of strands increases or the temperature decreases, the EEs localize, which is structurally reminiscent of a metal-insulator transition. Colloidal crystal metallicity, therefore, provides new routes to metallic, intermetallic, and compound phases.

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Particle shape effects in colloidal crystals and colloidal liquid crystals: Small-angle X-ray scattering studies with microradian resolution

Current Opinion in Colloid & Interface Science ◽

10.1016/j.cocis.2015.09.003 ◽

2015 ◽

Vol 20 (4) ◽

pp. 272-281 ◽

Cited By ~ 33

Author(s):

Andrei V. Petukhov ◽

Janne-Mieke Meijer ◽

Gert Jan Vroege

Keyword(s):

Liquid Crystals ◽

Small Angle ◽

Particle Shape ◽

Colloidal Crystals ◽

X Ray ◽

X Ray Scattering ◽

Shape Effects ◽

Ray Scattering

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Intermediate crystalline structures of colloids in shape space

Soft Matter ◽

10.1039/c8sm01573b ◽

2018 ◽

Vol 14 (43) ◽

pp. 8692-8697 ◽

Cited By ~ 11

Author(s):

Daphne Klotsa ◽

Elizabeth R. Chen ◽

Michael Engel ◽

Sharon C. Glotzer

Keyword(s):

Particle Shape ◽

Colloidal Crystals ◽

Shape Space ◽

Convex Polyhedra ◽

Systematic Design ◽

Triangle Groups ◽

Crystalline Structures ◽

Self Assembling

We computationally study the thermodynamic assembly of more than 40 000 hard, convex polyhedra belonging to three families of shapes associated with the triangle groups 323, 423, and 523. Our results provide a guide to self-assembling a host of related colloidal crystals through systematic design, through careful tweaking of particle shape.

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Dielectrophoretic assembly of dimpled colloids into open packing structures

Soft Matter ◽

10.1039/c7sm00874k ◽

2017 ◽

Vol 13 (34) ◽

pp. 5724-5730 ◽

Cited By ~ 5

Author(s):

Zhuoqiang Jia ◽

Stefano Sacanna ◽

Stephanie S. Lee

Keyword(s):

Phase Transitions ◽

Solid State ◽

Electric Field ◽

Particle Shape ◽

Colloidal Crystals ◽

Shape Anisotropy ◽

Two Dimensional ◽

Open Packing

Particle shape anisotropy enabled electric field-induced reversible solid-state phase transitions in two-dimensional colloidal crystals comprising dimpled spherical colloids.

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Phase behavior of cationic and anionic surfactants at low concentrations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123878 ◽

1992 ◽

Vol 50 (1) ◽

pp. 694-695

Author(s):

E. Naranjo

Keyword(s):

Phase Behavior ◽

Structural Characterization ◽

Dynamic Systems ◽

Anionic Surfactants ◽

Intermolecular Forces ◽

Stable Form ◽

Surfactant Mixtures ◽

Low Concentrations ◽

Cationic And Anionic Surfactants ◽

General Method

Equilibrium vesicles, those which are the stable form of aggregation and form spontaneously on mixing surfactant with water, have never been demonstrated in single component bilayers and only rarely in lipid or surfactant mixtures. Designing a simple and general method for producing spontaneous and stable vesicles depends on a better understanding of the thermodynamics of aggregation, the interplay of intermolecular forces in surfactants, and an efficient way of doing structural characterization in dynamic systems.

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