Dynamics of DNA-programmable nanoparticle crystallization: gelation, nucleation and topological defects

DNA programmed nanoparticle self-assembly is emerging as a powerful technique to engineer novel materials. In this paper, we present a comprehensive characterization of the dynamics of DNA mediated nanoparticle superlattice self-assembly from numerical simulations. We show that crystallization is consistent with classical nucleation theory, where the supercooled phase is a gel and the internal energy of the system remains constant during crystallization. After crystallization occurs, equilibrium is reached only after substitutionals, the most common topological defects, are annihilated in a process that involves vacancies or interstitials. Implications for existing and future experiments, as well as for engineering high quality, even single crystal, superlattices are also discussed.