Dynamic, self-assembled aggregates of magnetized, millimeter-sized objects rotating at the liquid-air interface: Macroscopic, two-dimensional classical artificial atoms and molecules

Both the hydrodynamic repulsive force between the disks and the central magnetic force acting on all disks were quantified. Two types of aggregates were considered: those in which one disk is much larger than the others and those in which two disks are larger than the rest. It was demonstrated that the self-assembly of spinning disks into macroscopic artificial atoms and molecules is the consequence of the interplay between attractive and repulsive interactions.