(268d) Inverse Design of Pairwise Interactions for Self-Assembly of Low-Coordinated Lattice Structures

Engineering the effective interactions between suspended nanoparticles or colloids to promote their assembly into specific lattice structures is an important and rapidly growing area of soft-matter research. Low-coordinated (e.g., diamond) crystals are often chosen to be the “target” lattices in such studies due to their potential as novel structures for photonic band gap materials. Computer simulations have shown that particles with anisotropic (“patchy”) interactions can spontaneously form such equilibrium structures [1-5]. However, whether simpler isotropic interactions can also be designed to drive self-assembly into low-coordinated lattice structures – with perhaps more favorable kinetics than systems with anisotropic interactions— is a long-standing open question. In this study, we use inverse statistical mechanical methods to derive simple, repulsive pair potentials that display diamond and other low-coordinated ground states [6,7]. We characterize aspects of the equilibrium and dynamic behavior of these model systems and discuss their experimental realizability in polymeric colloidal materials.

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