title: On the modeling of aggregates of an optically active regioregular polythiophene.
abstract: The conformational properties of the optically active regioregular poly[(R)-3-(4-(4-ethyl-2-oxazolin-2-yl) phenyl) thiophene] (PEOPT) were explored by molecular dynamics on a single chain using several solvents of increasing polarity. Furthermore, their aggregate formation was studied over a wide range of temperatures using a replica exchange molecular dynamics simulation providing simulation data representative of the equilibrium behaviour of their aggregates. Results show a clear tendency of PEOPT to keep a syn-gauche conformation between continuous backbone thiophene rings favouring a bent chain structure in solvent. After studying their aggregation behaviour in acetonitrile, a strong tendency to pack stabilizing structures that reinforce the chirality of the polymer, in concordance with experimental data, was found. Two different aggregated structures were observed depending on oligomer length, a self-assembled helical aggregate based on stacked octamers and a bent double helix aggregate in large oligomers.
authors.affiliation: Departament d'Enginyeria Química, Escola d'Enginyeria d'Igualada, Universitat Politècnica de Catalunya, Pça. Rei 15, 08700 Igualada, Spain. joan.torras@upc.edu
authors.forename: Juan
authors.initials: J
authors.lastname: Torras
authors.forename: Cristina
authors.initials: C
authors.lastname: Sanchez-Navas
authors.forename: Oscar
authors.initials: O
authors.lastname: Bertran
authors.forename: Carlos
authors.initials: C
authors.lastname: Alemán