Programmable Potentials Choreograph Defects in a Colloidal Crystal Shell.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Crystallization on spherical surfaces inherently creates lattice defects due to topological constraints.
• Controlling defect organization on curved surfaces is challenging due to long-range geometric effects.

Purpose of the Study:

• To demonstrate control over defect arrangement in spherical crystallization.
• To achieve specific crystal geometries, such as perfect icosahedral order, on a sphere.
• To provide a tunable system for studying crystallization physics on curved substrates.

Main Methods:

• Utilized DNA-coated colloids with programmable interaction potentials.
• Employed combined molecular simulations and theoretical analysis.
• Varied temperature to tune interaction potentials and control defect formation.

Main Results:

• Successfully regulated the arrangement of lattice defects on a spherical surface.
• Achieved perfect icosahedral crystalline order on the sphere.
• Derived an explicit expression for the effective potential, distinguishing entropic and enthalpic contributions.

Conclusions:

• Programmable DNA-coated colloids offer a method to control defect organization in spherical crystallization.
• Temperature tuning of interaction potentials dictates defect density and arrangement.
• Findings offer insights into the physics of crystallization on curved surfaces and guide the design of novel crystal geometries.