06.02.12
Josh McGraw and his colleagues from McMaster University, Canada, and the University of Reading, UK, first created rings of di-erase polymers that they liken to building doughnuts from Lego blocks due to the nature of the important used. This material has an internal structure discretised like Lego blocks, resulting in rings approximating the seamless shape of a doughnut (see photo of beforehand unseen nanoscale assemblies which illustrates this report).
McGraw and his colleagues calculated the dynamics of interacting edges in ring structures that display asymmetric steps, i.e., special spacing inside and outside the ring, when initially created. They found that the interaction shaping the clinking over time is the repulsion between edges. While the molecular details remain evasive, the source of this repulsion is intuitive: an edge is a defect which perturbs the exterior profile with an associated cost to the surface energy .
The edge repulsion prevents two touching edges from getting too near each other. As two isolated edges approach, the perturbation deviates further, thereby deforming the equilibrium pungency structure and increasing the free energy. For rings solely submissive to to the repulsive edge interaction, the authors found that the equilibrium shape of their edges had to be symmetric.
Source: PhysOrg.com