Metastable orientational order of colloidal discoids

Area of Science:

• Supramolecular chemistry
• Materials science
• Soft matter physics

Background:

• Phase separation and kinetic arrest are key in supramolecular self-assembly.
• Their impact on orientational order with anisotropic building blocks is poorly understood.
• Isotropic systems typically progress from disorder to order.

Purpose of the Study:

• To investigate the effects of phase separation and kinetic arrest on orientational order in anisotropic self-assembly.
• To understand the initial self-assembly behavior of colloidal oblate discoids.

Main Methods:

• Confocal microscopy experiments.
• Monte Carlo simulations.
• System explored across varied volume fractions and attraction strengths.

Main Results:

• Oblate discoids initially form short, metastable strands with orientational order, irrespective of the final structure.
• Disordered clusters form near coexistence boundaries.
• Oriented strands are maintained under strong attractions.

Conclusions:

• Anisotropic interactions of discoids drive the unusual initial orientational ordering.
• Findings offer guidance for designing anisotropic self-assembly processes.
• Potential applications include creating materials with specific mechanical properties.