Aesthetics of assembly of giant molecules under precision synthesis

Abstract

The problems to efficiently and robustly pack the objects together have been studied for centuries due to their mathematic aesthetics and direct applications to understand the myriad phase structures compacted from spherical metallic atoms to other polyhedral building blocks. For the simplest polyhedron, rigid tetrahedra were shown to form crystalline and quasi-crystalline phases by analytical calculations or computer simulations if only packing or shape entropy dominates the free energy. However, related experimental observations of the structures or their formation mechanisms are remained largely unexplored, possibly mainly due to two reasons: firstly, enthalpy interaction in real system cannot be ruled out as in modeling, and secondly, precise control of the shape and tuning of the enthalpy interaction of the building blocks are so far extremely challenging experimentally. Recently, Prof. Stephen Z. D. Cheng from University of Akron and his collaborators including Dr. Wen-Bin Zhang from Peking University have represented a rigorous work to show how to control the selective assembly of a class of nanosized giant tetrahedra by precisely mediating the interactions between the tetrahedra and the overall molecular geometry.