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

Jain, A., The University of Texas at Austin

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.

[1] Z.L Zhang, A.S Keys, T. Chen, S.C Glotzer, ‘Self-Assembly of patchy particles into diamond structures through molecular mimicry’, Langmuir, 21, pp. 11547-11551 (2005)

[2] Z.L Zhang, S.C Glotzer, ‘Self Assembly of patchy particles’, Nano Letters, 204, pp. 1407-1413 (2004)

[3] F. Romano, F.Sciortino, ‘Colloidal self-assembly: Patchy from bottom up’, Nature Materials, 10, 171-173 (2011)

[4] F. Romano, E. Sanz, F.Sciortino, ‘Phase Diagram of a tetrahedral patchy particle model for different interaction ranges’, Journal of Chemical Physics, 132, 184501 (2010)

[5] E. Bianchi, R. Blaak, C.N Likos, ‘Patchy Colloids: state of the art and perspectives’, Physical Chemistry Chemical Physics, 13, pp.6397-6410 (2011)

[6] S. Torquato, ‘Inverse Optimisation techniques for targeted self-assembly’, Soft Matter, 5, pp. 1157-1173 (2009)

[7] E. Marcotte, F.H Stillinger, S.Torquato, ‘Unusual ground states via monotonic convex pair potentials’, Journal of Chemical Physics, 134, 164105 (2011)

See more of this Session: Computational Studies of Self-Assembly II

See more of this Group/Topical: Engineering Sciences and Fundamentals