title: Theory of non-Condon emission from the interchain exciton in conjugated polymer aggregates.
abstract: The authors present here a simple analysis that explains the apparent strengthening of electron phonon interaction upon aggregation in conjugated polymer materials. The overall scheme is that of an intermolecular Herzberg-Teller effect whereby sidebands of a forbidden transition are activated by oppositely phased vibrations. The authors show that upon aggregation, the 0-0 emission becomes symmetry forbidden and the apparent redshift and remaining vibronic structure are due to sideband (0-1,0-2, etc.) emission. At higher temperatures, the 0-0 peak is due to thermal population in a higher lying even-parity vibronic state rather than direct emission from the odd-paritied lowest intermolecular vibronic state.
authors.affiliation: Texas Center for Superconductivity, Department of Chemistry, University of Houston, Houston, Texas 77204, USA. bittner@uh.edu
authors.forename: Eric R
authors.initials: ER
authors.lastname: Bittner
authors.forename: Stoyan
authors.initials: S
authors.lastname: Karabunarliev
authors.forename: Laura M
authors.initials: LM
authors.lastname: Herz