(606f) Designing Interactions That Stabilize Assemblies to Changes in Density or Temperature: Application to Square, Snub Square and Kagome Lattices

Manufacture of materials with specific morphologies for novel applications (e.g. photonics) remains a formidable challenge. While some design control is possible at nanometer length scales using top-down fabrication approaches, bottom-up self-assembly of a targeted material structure presents an alternative that, in some cases, may be less expensive and more robust. Design methods for determining the interactions required for targeted assembly fall under the category of â??forwardâ?? methods, whereby a systematic discovery of equilibrium structures is made from a given interaction form; or â??inverse methodsâ??, whereby a desired structure is targeted as the thermodynamically stable structure, and the tunable interaction parameters required to establish it found via a constrained optimization. Here, we demonstrate that the optimization of potential parameters for ground state assembly can be formulated analytically as a non-linear problem, which can then be solved numerically with, e.g., the mathematical modeling software GAMS (Generalized Algebraic Modeling System). This formulation allowed us to recently test how the interaction required for assembly might be constrained to favor structures that are unusually stable to changes in temperature or density. We discuss the implications of our approach for the design of soft repulsive interactions that assemble into square [1], snub square, and kagome lattices [2].

[1] W. D. Piñeros, M. Baldea, T. M.Truskett, J. Chem. Phys. 144, 084502 (2016)

[2] W. D. Piñeros, M. Baldea, T. M. Truskett, submitted (2016)