title: Hopping transport in conductive heterocyclic oligomers: reorganization energies and substituent effects.
abstract: Molecular scale charge motion in disordered organic materials at ambient temperature occurs via a hopping-type mechanism with rates dictated both by the charge transfer integral and by the reorganization energy due to geometric relaxation. This contribution presents a systematic theoretical analysis of cation internal reorganization energies for a broad family of organic oligoheterocycles-variation of reorganization energy with oligomer chain length, heteroatom identity, and a range of heterocycle substituents provides key information on important structural properties governing internal reorganization energies. At room temperature, the range in reorganization energies induced by substituent variations corresponds to a >10(2)-fold variation in intrinsic hole transfer rate, suggesting that changes in reorganization energy dominate variations in charge-transfer rates for many semiconducting/conducting oligomers.
authors.affiliation: Department of Chemistry and the Materials Research Center, Northwestern University, Evanston, Illinois 60208-3113, USA.
authors.forename: Geoffrey R
authors.initials: GR
authors.lastname: Hutchison
authors.forename: Mark A
authors.initials: MA
authors.lastname: Ratner
authors.forename: Tobin J
authors.initials: TJ
authors.lastname: Marks