title: Predicting properties of organic optoelectronic materials: asymptotically corrected density functional study.
abstract: A practical computational procedure has been proposed that provides key electronic parameters of a polymer (fundamental bandgap, ionization energy, electron affinity, and intrachain electron and hole mobilities) determining its suitability as a donor or acceptor in organic optoelectronic materials. Series of oligomer calculations at the Becke3-Lee-Yang-Parr level with and without a self-contained asymptotic correction using the 6-31G** basis set were performed. The bandgap, ionization energy, and electron affinities of a polymer are extrapolated from those of its oligomers obtained from the highest occupied and lowest unoccupied orbital energies in the Koopmans-like approximation. This scheme has been applied to conjugated polymers having the poly(p-phenylene), poly(thiophene), or poly(pyrrole) backbone as well as to PCBM. The observed values of the electronic parameters have been reproduced within less than 1 eV in most cases. With the predicted values of these parameters, estimates of the open-circuit voltage and drift potential have been made for 22 valid donor-acceptor combinations. Several potentially useful combinations have been identified including the poly(thiophene):PCBM. The electron and hole mobilities have been found to correlate more strongly with the conformation (planarity) than the bandgap, but otherwise do not differ significantly.
authors.affiliation: Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: Archana
authors.initials: A
authors.lastname: Rajendran
authors.forename: Takashi
authors.initials: T
authors.lastname: Tsuchiya
authors.forename: So
authors.initials: S
authors.lastname: Hirata
authors.forename: Tzvetelin D
authors.initials: TD
authors.lastname: Iordanov
mesh_terms: D055620:Optical Phenomena; D009930:Organic Chemicals / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D009930:Organic Chemicals; D011108:Polymers