Dissipative particle dynamics simulation of T- and X-shaped polyphilic molecules exhibiting honeycomb columnar phases

Dissipative particle dynamics simulations are used to investigate the structure of the columnar phases in T- and X-shaped bolaamphiphiles. These amphiphilic molecules consist of a rod-like aromatic core, with a polar group at each end. A single lateral chain is present in the T- shaped molecules and two lateral chains are present for X-shaped molecules. The simulations indicate that both types of molecules exhibit square and hexagonal columnar phases, in which the walls of the columns are formed by the aromatic core, the polar groups are located at the edges and the lateral chains fill the interiors of the columns. For the T- shaped molecules, the columns are always double walled. In contrast, for the X-shaped molecules, the columnar phases are single walled, in agreement with X-ray diffraction studies.