Self-assembly pathways towards floppy colloidal square lattices

Nature Communications, vol. 17, pp. 1040

Abstract

The ability to rearrange is crucial for the function of proteins and biopolymers and governs many properties of materials. While rearranging bonds are needed to create floppy structures, it has remained largely unexplored how they affect the self-assembly pathways. We here use a binary colloidal model system equipped with surface-mobile DNA-based bonds to study how regular structures with tunable flexibility and square network symmetry can be created through self-assembly. We find that reconfigurability during self-assembly leads to lattices with square symmetry which are inherently mechanically unstable and hence thermally floppy. By considering the role of size ratio, number ratio, and directionality induced by particle shape, we identify the pathways that maximize the yield and flexibility of these square lattices using a combination of experiments, analytical calculations, and simulations. Our study highlights the crucial role of reconfigurability in systems that are governed by enthalpic and entropic principles, from synthetic to biological, and might be useful for creating materials with novel or reconfigurable properties. Rearrangements govern many properties of materials and molecules, but it has been largely unexplored how to create flexible structures from the bottom up. Here, the authors use colloidal particles to explore how to guide the kinetic self-assembly pathways into ordered structures that maintain flexibility.

Authors 3

1. Yogesh G. Shelke Aachen Soft Matter Physics Huygens-Kamerlingh Onnes Laboratory

   Leiden University

   Affiliation as printed

   Soft Matter Physics, Huygens-Kamerlingh Onnes Laboratory, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands

2. Daniel J. Pearce

   University of Geneva

   Affiliation as printed

   Department of Theoretical Physics, École de Physique, University of Geneva, Geneva, Switzerland

3. Daniela J. Kraft corresponding Aachen Soft Matter Physics Huygens-Kamerlingh Onnes Laboratory

   Leiden University

   Affiliation as printed

   Soft Matter Physics, Huygens-Kamerlingh Onnes Laboratory, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands. kraft@physics.leidenuniv.nl