Soap froths and crystal structures

We propose a physical mechanism to explain the crystal symmetries found in macromolecular and supramolecular micellar materials. We argue that the pac king entropy of the hard micellar cores is frustrated by the entropic inter action of their brushlike coronas. The latter interaction is treated as a s urface effect between neighboring Voronoi cells. The observed crystal struc tures correspond to the Kelvin and Weaire-Phelan minimal foams. We show tha t these structures are stable for reasonable areal entropy densities.