Entropically driven self-assembly of star-shaped micelles in pear-sphere-mixtures

Improvements in the synthesis of colloids mean that a great variety of complex aspherical
shapes have become an experimental reality. Motivated by the possibility of a wide range of new phases, computational studies address the particle shape dependence of the colloidal self-assembly process.

Tapered ellipsoids, reminiscent of "pear-shaped" particles, have not been realised in experiments yet. Previous
computational studies showed, however, that these pear assemblies form bicontinuous cubic gyroid phases,
similar to those famously found in various biological lipid bilayer systems.

Based on these methods, we investigate an earlier stage of this self-assembly, namely the formation of
structures from a small number of pears in a 'bath' of hard spheres. We observe the formation of star-like
micellar structures. We perform Monte Carlo simulations with two different tapered particles, pears and tapered spherocylinders, and compare their capability to form these clusters. In addition we investigate systems where the micelles themselves form bigger, potentially cubic phases in a hierarchical fashion. These results will inform a deeper understanding of the formation of bicontinuous structures in nature and a notion of the similarities and differences between enthalpic and entropic self-assembly.