Universal two-step crystallization of DNA-functionalized nanoparticles

TL;DR

This study reveals that DNA-functionalized nanoparticles crystallize through a universal two-step process involving an amorphous intermediate, with crystallization only occurring within a specific temperature range, similar to proteins and colloids.

Contribution

It demonstrates the universal two-step crystallization mechanism of DNA-functionalized nanoparticles and identifies the temperature-dependent kinetic barriers involved.

Findings

Crystallization occurs only within a narrow temperature window.

Crystallization proceeds via a two-step process with an amorphous intermediate.

Lower temperatures hinder crystallization due to slow unzipping dynamics.

Abstract

We examine the crystallization dynamics of nanoparticles reversibly tethered by DNA hybridization. We show that the crystallization happens readily only in a narrow temperature "slot," and always proceeds via a two-step process, mediated by a highly-connected amorphous intermediate. For lower temperature quenches, the dynamics of unzipping strands in the amorphous state is sufficiently slow that crystallization is kinetically hindered. This accounts for the well-documented difficulty of forming crystals in these systems. The strong parallel to the crystallization behavior of proteins and colloids suggests that these disparate systems crystallize in an apparently universal manner.