From nuclei to micro-structure in colloidal crystallization: Investigating intermediate length scales by small angle...

Area of Science:

• Statistical physics
• Soft condensed matter physics
• Materials science

Background:

• Hard sphere suspensions are fundamental models in statistical physics and soft condensed matter.
• Understanding crystallization kinetics and micro-structure evolution is crucial for materials science applications.

Purpose of the Study:

• To investigate the temporal evolution of crystal nucleation and growth environments in hard sphere suspensions.
• To analyze the impact of preparation conditions on crystallization kinetics and final micro-structure.
• To identify and characterize the physical processes underlying observed scattering signals.

Main Methods:

• Utilizing time-resolved Small Angle Light Scattering (SALS) to monitor large-scale structural changes.
• Employing simultaneous Bragg scattering for precise temporal event sequencing.
• Analyzing diverse SALS signal shapes and their temporal evolution.

Main Results:

• Different preparation conditions result in distinct large-scale processes influencing crystallization kinetics and micro-structure.
• SALS signals were identified as form factor scattering from crystals with depletion zones and structure factor scattering from inter-crystallite ordering.
• The study observed a wide variety of SALS signals, providing complementary information to Bragg scattering and microscopy.

Conclusions:

• SALS analysis reveals significant micro-structural evolution during re-crystallization in hard sphere systems.
• The observed scattering signals offer insights into processes occurring at length scales beyond the structural scale.
• Further theoretical refinement is needed for quantitative kinetic analysis of micro-structural evolution from SALS data.