pH-Controlled Self-Assembly of X-Shaped Conjugated Molecules: The Case of 1,2,4,5-Tetrastyrylbenzene

The control of the self-assembly of organic material compounds has a significant impact on different technological, biomedical, and sensing applications. In this work we have studied the influence of the nature of the side chain on the one-dimensional self-assembly of X-shaped conjugated molecules based on 1,2,4,5-tetrastyrylbenzene cores. This phenomenon was first studied in solution by means of different spectroscopic techniques, and the experimental observations were compared to the behavior of a homologous compound with Y-shape, based on a 1,3,5-tristyrylbenzene core. The aggregation state of these compounds was controlled by the pH and temperature of the medium. Density functional theory calculations allowed us to better understand protonation equilibria related to aggregation processes. Finally, the supramolecular ordering of the set of X-shaped molecules studied here in the solid phase was analyzed through transmission electron microscopy.