Self-assembly of reconfigurable colloidal molecules.

Area of Science:

• Colloidal science
• Materials science
• Soft matter physics

Background:

• Sacanna et al. introduced lock-and-key colloidal particles as dynamic building blocks.
• These particles feature a central 'key' and rotatable 'lock' components bound by depletion interactions.
• The rotational freedom of locks provides mechanical reconfigurability to these colloidal molecules.

Purpose of the Study:

• To predict the self-assembly of lock-and-key colloidal particles into complex crystalline structures using molecular simulation.
• To investigate how reconfigurability dimensions influence the resulting crystalline architectures.
• To demonstrate the formation of kinetically inaccessible ordered structures through reconfigurability.

Main Methods:

• Utilized molecular simulation techniques.
• Investigated self-assembly of lock-and-key colloidal building blocks.
• Analyzed the impact of reconfigurability dimensions: number of locks, bond length, size ratio, confinement, and lock mobility.

Main Results:

• Predicted self-assembly into a diverse range of complex crystalline structures.
• Demonstrated tunability of structures via reconfigurability dimensions.
• Achieved assembly of ordered structures, such as random triangle square tilings, which are kinetically inaccessible for non-reconfigurable counterparts.

Conclusions:

• Lock-and-key colloidal particles with mechanical reconfigurability enable the formation of complex and tunable crystalline materials.
• Reconfigurability is a key factor in overcoming kinetic limitations for assembling specific ordered structures.
• This work opens new avenues for designing advanced colloidal materials with programmable properties.