Molecular Arrangements of Regioregular and Regiorandom Poly(3-hexylthiophene): Molecular Dynamics Simulations

Abstract

  We studied the effects of regioregularity of the poly(3-hexylthiophene) (P3HT) molecules on the order of molecular arrangement in the P3HT lamellar structure using molecular dynamics simulations. We found that the RR-P3HT molecule shows the aligned molecular arrangement in the ordered lamellar structure, while the RRa-P3HT molecule produces disorders in the π-π interchain stacking due to the formation of disordered network of intermolecular interactions between alkyl side chains of the P3HT molecules. RR-P3HT gains more stabilization energy with respect to the intermolecular interactions than RRa-P3HT due to the formation of ordered lamellar structure in the former system. The order of molecular arrangement in the P3HT lamellar structure is considered to be controlled by the intermolecular interactions between the alkyl side chains.