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arXiv · 2606.15415

Kinetic Criticality in Linker-Mediated Colloidal Aggregation

Alexei V. Tkachenko·Soojung Lee·Zohar A. Arnon·Oleg Gang
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Abstract

Linker-mediated aggregation plays an important role in modern nanoscience. We demonstrate that it departs sharply from classical Smoluchowski kinetics because cluster reactivity evolves during growth. Combining theory with DNA-linked gold-nanoparticle experiments, we establish kinetic critical point controlled by linker abundance. Below threshold, active linkers are depleted and growth arrests; above threshold, clusters accumulate reactive sites, self-accelerate, and cross over to diffusion-limited coarsening. Experiments verify the predicted arrest, accelerated growth, and scaling collapse.

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Alexei V. Tkachenko, Soojung Lee, Zohar A. Arnon, Oleg Gang. 2026-06-13. Kinetic Criticality in Linker-Mediated Colloidal Aggregation. https://arxiv.org/abs/2606.15415

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