title: STM study on the self-assembly of oligothiophene-based organic semiconductors.
abstract: The self-assembly properties of a series of functionalized regioregular oligo(3-alkylthiophenes) were investigated by using scanning tunneling microscopy (STM) at the liquid-solid interface under ambient conditions. The characteristics of the 2-D crystals formed on the (0001) plane of highly ordered pyrolitic graphite (HOPG) strongly depend on the length of the π-conjugated oligomer backbone, on the functional groups attached to it, and on the alkyl substitution pattern on the individual thiophene units. Theoretical calculations were performed to analyze the geometry and electronic density of the molecular orbitals as well as to analyze the intermolecular interactions, in order to obtain models of the 2-D molecular ordering on the substrate.
authors.affiliation: Institute of Organic Chemistry II and Advanced Materials, Ulm University, Albert-Einstein-Allee 11, D 89081 Ulm, Germany.
authors.forename: Elena
authors.initials: E
authors.lastname: Mena-Osteritz
authors.forename: Marta
authors.initials: M
authors.lastname: Urdanpilleta
authors.forename: Erwaa
authors.initials: E
authors.lastname: El-Hosseiny
authors.forename: Berndt
authors.initials: B
authors.lastname: Koslowski
authors.forename: Paul
authors.initials: P
authors.lastname: Ziemann
authors.forename: Peter
authors.initials: P
authors.lastname: Bäuerle