title: Photohole screening effects in polythiophenes with pendant groups.
abstract: We compare two mechanisms that dominate the temperature-dependent changes in electronic structure for poly(3-hexylthiophene-2,5 diyl) (P3HT). Structural changes in the relative orientation and configuration of the aromatic ring backbone are observed to occur over a wide range in temperature and affect the local final state screening in photoemission. There are also changes in conductivity and carrier concentration at lower temperatures leading to altered long-range intramolecular screening of photoholes and final state effects that affect excitation spectroscopies including photoemission. For polyethylenedioxythiophene (PEDOT), temperature-dependent changes in the structure and configuration of the polymer backbone are not as significant, although temperature-dependent final state effects are observed.
authors.affiliation: Department of Physics and Astronomy and the Center for Materials Research and Analysis, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0111, USA.
authors.forename: D-Q
authors.initials: DQ
authors.lastname: Feng
authors.forename: A N
authors.initials: AN
authors.lastname: Caruso
authors.forename: D L
authors.initials: DL
authors.lastname: Schulz
authors.forename: Ya B
authors.initials: YB
authors.lastname: Losovyj
authors.forename: P A
authors.initials: PA
authors.lastname: Dowben