Engineering Azeotropy to Optimize the Self-Assembly of Colloidal Mixtures

Abstract

The goal of inverse self-assembly is to design interparticle interactions capable of assembling the units into a desired target structure. The effective assembly of complex structures often requires the use of multiple components, each new component increasing the thermodynamic degrees of freedom and, hence, the complexity of the self-assembly pathway. In this work we explore the possibility to use azeotropy, i.e., a special thermodynamic condition where the system behaves effectively as a one-component system, as a way to control the self-assembly of an arbitrary number of components. Exploiting the mass-balance equations, we show how to select patchy particle systems that exhibit azeotropic points along the desired self-assembly pathway. As an example we map the phase diagram of a binary mixture that, by design, fully assembles into cubic (and only cubic) diamond crystal via an azeotropic point. The ability to explicitly include azeotropic points in artificial designs reveals effective pathways for the self-assembly of complex structures.

Inverse design of a pyrochlore lattice of DNA origami through model-driven experiments

“…Our computational tools can be generalized to also design and guide the experimental realization of other types of lattices ( 36 ). The pipeline presented is not limited to long-range structures but can be just as easily exploited to realize finite-size assemblies ( 42 ) and azeotropic mixtures ( 43 ). The method could also be used to design initial seeding substructures for improving the yields and resulting sizes of the seeded nucleation and growth of the lattice, as well as design other sought-after lattice geometries such as clathrates ( 44 ).…”