Morphology and mobility of synthetic colloidal aggregates

Area of Science:

• Physics
• Materials Science
• Chemistry

Background:

• Fractal-like aggregates exhibit complex structures relevant to various scientific fields.
• Understanding the relationship between geometric and dynamic properties is crucial for predicting aggregate behavior.

Purpose of the Study:

• To investigate the link between geometric and dynamic properties of fractal-like aggregates.
• To develop a novel method for predicting aggregate hydrodynamic radius.
• To analyze the role of fractal dimension and prefactor in aggregate morphology.

Main Methods:

• Generation of synthetic aggregates using a cluster-cluster aggregation algorithm.
• Analysis of morphological features to determine fractal dimension and prefactor.
• Calculation of hydrodynamic radius via molecule-aggregate collision rates using Laplace equation solution.

Main Results:

• Fractal dimension describes large-scale structure; fractal prefactor indicates local structure and shape anisotropy.
• An empirical expression relating hydrodynamic radius to radius of gyration and particle number was proposed.
• The new expression, dependent only on geometry, accurately predicts hydrodynamic radius.

Conclusions:

• Geometric properties alone can effectively predict the hydrodynamic radius of fractal-like aggregates.
• The proposed empirical expression offers a simplified and accurate approach compared to statistical methods.
• Findings advance the understanding of aggregate dynamics and morphology.