title: Optical spectroscopy of a polyfluorene copolymer at high pressure: intra- and intermolecular interactions.
abstract: We present optical spectroscopy studies of the conjugated polymer poly(9,9-di-n-octylfluorene-alt-benzothiadiazole) (F8BT) at high pressure. The photoluminescence spectrum of F8BT in a dilute solid-state solution in polystyrene redshifts by 320 meV over 7.4 GPa, while that of a F8BT thin film redshifts 460 meV over a comparable pressure range. We attribute the redshift in solution to intrachain pressure effects, principally conformational planarization. The additional contribution from interchain pi-electron interactions accounts for the larger redshift of thin films.
authors.affiliation: Cavendish Laboratory, University of Cambridge, J. J. Thompson Avenue, Cambridge CB3 0HE, United Kingdom. jpschmidtke@gmail.com
authors.forename: Johanna P
authors.initials: JP
authors.lastname: Schmidtke
authors.forename: Ji-Seon
authors.initials: JS
authors.lastname: Kim
authors.forename: Johannes
authors.initials: J
authors.lastname: Gierschner
authors.forename: Carlos
authors.initials: C
authors.lastname: Silva
authors.forename: Richard H
authors.initials: RH
authors.lastname: Friend