Self-Assembly of Oligo(phenylene-thiophene)s on Monolayer Graphene: Molecular Dynamics Simulations

The problem of developing conducting molecular wires has recently received increased attention. We present the results of molecular dynamics simulations aimed at investigating the self-organization process of conjugated 2,5-dialkoxy-phenylene-thiophene-based oligomers (TBT) on a monolayer graphene over a wide range of temperatures. The local structural characteristics of the TBT oligomers and the macroscopic characteristics of their aggregates are investigated. It is shown that electrostatic interactions significantly affect the local structural characteristics of the molecules resulting in liquid-crystalline type of ordering of the oligomers on graphene. It is also found that the length of the oligomers assures the structural stability of ordered aggregates even at elevated temperatures.