title: Effect of Side Chains on Molecular Conformation of Anthracene-Ethynylene-Phenylene-Vinylene Oligomers: A Comparative Density Functional Study With and Without Dispersion Interaction.
abstract: Using density functional calculations with and without dispersion interaction, we studied the effects of linear octyl and branched 2-ethylhexyl side chains on the oligomer conformation of the conjugated copolymer poly(p-anthracene-ethynylene)-alt-poly(p-phenylene-vinylene). With dispersion included, the branched side chains can cause significant bending of the oligomer backbone, while without dispersion they induce mainly torsional disorder. The oligomers with mainly linear side chains keep good planarity when optimized with and without dispersion. Despite their dramatically different conformations, the calculated absorption spectra of the oligomers with various side chain combinations are very similar, indicating that the conformation of the copolymer is not the main reason for the experimentally observed different spectra of ordered and disordered phases.
authors.affiliation: Institut für Physik and Institut für Mikro- und Nanotechnologie, Technische Universität Ilmenau , 98693 Ilmenau, Germany.
authors.forename: Chuanding
authors.initials: C
authors.lastname: Dong
authors.affiliation: Center for Energy and Environmental Chemistry Jena and Laboratory of Organic and Macromolecular Chemistry, Friedrich Schiller University Jena , 07743 Jena, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Hoppe
authors.affiliation: Institut für Physik and Institut für Mikro- und Nanotechnologie, Technische Universität Ilmenau , 98693 Ilmenau, Germany.
authors.forename: Wichard J D
authors.initials: WJ
authors.lastname: Beenken