(74d) Structural Transformations in Binary Superlattices of DNA-Functionalized Particles

Binary superlattices can be constructed through self-assembly of micron-sized DNA-functionalized particles (DFPs). The “multi-flavoring” approach to DNA functionalization, in which interactions between different types of particles in a binary mixture can be tuned independently, has been shown to yield a variety of compositionally ordered two-dimensional (2D) and three-dimensional (3D) structures. We demonstrate here how the stability of various crystalline phases is affected by crystal size, and how this relates to the mechanisms of crystal nucleation during self-assembly. Using a pairwise interaction model for micron-sized particles, we employ computational methods to understand the thermodynamic and kinetic factors contributing to transformations between structures. Additionally, we consider how reversible switching between lattices can be induced by changing temperature, which can be exploited to design useful reconfigurable materials.