Figure 1. The assembly of hollow superball colloids into different phases.

(a) Schematic representation of superball particles of which the corner roundness is described by the shape parameter m. (b) Transmission electron microscopy images of several of the hollow silica superball particles. (c) CLSM set-up of sedimentation experiment of superball particles onto a cover slide. (d) CLSM images obtained just above the glass wall of fluorescent superballs with m=3.0 showing the structural transition over time from a disordered fluid phase (F) to a PC and finally into a RC lattice consisting of stacked RC planes (see Supplementary Movie 1 for particle dynamics and Supplementary Fig. 1 for cross sections). (Insets) Fourier transform of time series of the respective phase. (e) Schematic representation of an RC plane described by lattice vectors a₁ and a₂ and their angle, α. The complete transition from a hexagonal to square lattice is described by a change in α from 120° to 90°. (f) Radial distribution functions g(r/L) extracted from the particle positions in the aligned lattice planes together with the expected positions for different rhombohedral lattice angles α. Scale bars are (b) 1 μm (d) 10 μm.