title: Impact of perfluorination on the charge-transport parameters of oligoacene crystals.
abstract: The charge-transport parameters of the perfluoropentacene and perfluorotetracene crystals are studied with a joint experimental and theoretical approach that combines gas-phase ultraviolet photoelectron spectroscopy and density functional theory. To gain a better understanding of the role of perfluorination, the results for perfluoropentacene and perfluorotetracene are compared to those for their parent oligoacenes, that is, pentacene and tetracene. Perfluorination is calculated to increase the ionization potentials and electron affinities by approximately 1 eV, which is expected to reduce significantly the injection barrier for electrons in organic electronics devices. Perfluorination also leads to significant changes in the crystalline packing, which greatly affects the electronic properties of the crystals and their charge-transport characteristics. The calculations predict large conduction and valence bandwidths and low hole and electron effective masses in the perfluoroacene crystals, with the largest mobilities expected along the pi-stacks. Perfluorination impacts as well both local and nonlocal vibrational couplings, whose strengths increase by a factor of about 2 with respect to the parent compounds.
authors.affiliation: School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA.
authors.forename: M Carmen Ruiz
authors.initials: MC
authors.lastname: Delgado
authors.forename: Kathryn R
authors.initials: KR
authors.lastname: Pigg
authors.forename: Demétrio A
authors.initials: DA
authors.lastname: da Silva Filho
authors.forename: Nadine E
authors.initials: NE
authors.lastname: Gruhn
authors.forename: Youichi
authors.initials: Y
authors.lastname: Sakamoto
authors.forename: Toshiyasu
authors.initials: T
authors.lastname: Suzuki
authors.forename: Reyes Malavé
authors.initials: RM
authors.lastname: Osuna
authors.forename: Juan
authors.initials: J
authors.lastname: Casado
authors.forename: Víctor
authors.initials: V
authors.lastname: Hernández
authors.forename: Juan Teodomiro López
authors.initials: JT
authors.lastname: Navarrete
authors.forename: Nicolas G
authors.initials: NG
authors.lastname: Martinelli
authors.forename: Jérôme
authors.initials: J
authors.lastname: Cornil
authors.forename: Roel S
authors.initials: RS
authors.lastname: Sánchez-Carrera
authors.forename: Veaceslav
authors.initials: V
authors.lastname: Coropceanu
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Brédas