Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5372838 | Chemical Physics | 2016 | 11 Pages |
A comprehensive DFT study of a set of oligo(p-phenylene vinylene) molecules is performed to understand the structural and electronic changes upon functionalization. These changes are rationalized within a model considering frontier molecular orbitals of the ππ-conjugated system and σσ-bonding orbital by which the functional group is attached to the host molecule. Two simple scalar quantum chemical descriptors are shown to correlate with optoelectronic properties of the functionalized molecule: the electronegativity and the relative electric dipole moment of the smallest ππ-closed shell subsystem containing the functional group and the terminal segment of the host molecule (phenyl). Both descriptors correlate linearly with the empirical Hammett σpσp constant for a set of 24 functional groups. Comparison with available experimental data on UV–vis absorption and cyclic voltammetry is made. Observed structural changes reflect changes in the electronic density.
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