title: Understanding optoelectronic properties of cyano-terminated oligothiophenes in the context of intramolecular charge transfer.
abstract: In this paper we have prepared a new series of oligothiophenes capped with hexyl groups and a variety of strong acceptors, mainly cyanovinyl moieties. An exhaustive analysis of the absorption, photophysical, electrochemical, solid state, nonlinear optical and vibrational properties has been presented guided by theoretical calculations. The investigation is centered on the efficiency of the intramolecular charge transfer (i.e., chain length and acceptor dependence) and its impact on all the relevant electronic, structural, optical, and vibrational properties. The most significant features imparted by the acceptors through the π-conjugated oligothiophene path are (i) intense visible electronic absorptions, (ii) tuned fluorescence wavelength emissions, (iii) solid state π-stacking, (iv) ambipolar redox behavior, (v) S(1) ⇝ S(0) internal conversion as being the major route for the deactivation of the excited state, and (vi) large electronic and vibrational contributions to their nonlinear optical response (hyperpolarizability). The analysis establishes connections between the different properties of the materials and structure-function relationships useful in organic electronics.
authors.affiliation: Department of Physical Chemistry, University of Málaga, Campus de Teatinos s/n, 29071 Málaga, Spain.
authors.forename: Sandra Rodríguez
authors.initials: SR
authors.lastname: González
authors.forename: Jesús
authors.initials: J
authors.lastname: Orduna
authors.forename: Raquel
authors.initials: R
authors.lastname: Alicante
authors.forename: Belén
authors.initials: B
authors.lastname: Villacampa
authors.forename: Kari A
authors.initials: KA
authors.lastname: McGee
authors.forename: João
authors.initials: J
authors.lastname: Pina
authors.forename: J Seixas
authors.initials: JS
authors.lastname: de Melo
authors.forename: Kathryn M
authors.initials: KM
authors.lastname: Schwaderer
authors.forename: Jared C
authors.initials: JC
authors.lastname: Johnson
authors.forename: Brady A
authors.initials: BA
authors.lastname: Blackorbay
authors.forename: Jacob J
authors.initials: JJ
authors.lastname: Hansmeier
authors.forename: Victoria F
authors.initials: VF
authors.lastname: Bolton
authors.forename: Tyler J
authors.initials: TJ
authors.lastname: Helland
authors.forename: Brett A
authors.initials: BA
authors.lastname: Edlund
authors.forename: Ted M
authors.initials: TM
authors.lastname: Pappenfus
authors.forename: Juan T López
authors.initials: JT
authors.lastname: Navarrete
authors.forename: Juan
authors.initials: J
authors.lastname: Casado