Unambiguous Determination of Electrostatically Driven Molecular Packing in a Triphenylene–Surfactant Complex Monolayer

Abstract

AbstractEmergence of ordered structures during molecular self‐assembly at interfaces is influenced by a variety of thermodynamic and kinetic factors that are not well understood. Experiments alone can only inform about the final architecture keeping self‐assembly pathways inaccessible. Here with the help of molecular dynamic simulations, the intricate details of the self‐assembly processes and resultant ordered structures of a triphenylene–surfactant complex monolayer at air–water interface are reported. The monolayer is observed to be stable and reversible using surface manometry and real‐time Brewster angle microscopy. Not only that the simulated isotherm and 2D density profiles are in good agreement with experimental observations, the simulation results bespeak the crucial role of specific electrostatic interactions forming the nanostructures at the interface analyzed via orientational structural profiles, radial distribution, and Z‐density profiles. Moreover, real‐space visualization using atomic force microscopy suggests that the molecular packing is preserved in the monolayer even after transferring onto a silicon substrate. Since the rational designing of organic electronics requires nanoscale control of molecular structures on solid substrates, it is anticipated that these results will be of fundamental importance.