(363g) Competing Structural Motifs in Confined Assemblies of Hard Tetrahedral Particles

Self-assembly simulations of polyhedra in confinement mimic processes such as the crowding of particles in evaporating droplets. Systems consisting of colloidal spheres confined in a droplet have been observed to form structures that are distinct from the bulk crystal up to tens of thousands of particles. Here, we extend this research to study a family of hard, tetrahedral particles using Monte Carlo simulations. By compressing the particles in a shrinking container to model confined assembly, we examine how changing shape and system size affect the accessible motifs. We analyze the prevalence of different local geometries as the particle shape varies from a tetrahedron via vertex truncation. As we examine the transformation from a confined structure to a bulk-like one with increasing system size, we observe that tetrahedral particles assemble in distinct shell-like arrangements up to very high numbers of particles, accompanied by a shift in the dominant structural motifs for certain shapes.