Dergiler / Turkish Journal of Chemistry / 2009 / Cilt: 33 - Sayı: 6

A highly soluble asymmetric perylene-bis (dicarboximide)-acceptor system incorporating a methylene bridged methoxybenzene-donor: solvent dependence of charge transfer interactions

Sayfa
727–737
DOI
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Özet

The synthesis and photophysical properties of an asymmetrically substituted perylene-bis(dicarboximide), (PDI), system (1) containing a methylene bridged 4-methoxy-benzene donor and a solubilizing branched C13 alkyl chain are described. As compared to most PDIs, the fluorescence of 1 is strongly quenched in polar (but not in non-polar) solvents due to a photo-induced electron transfer process. Transient absorption spectroscopy and time resolved emission in e.g. acetonitrile indicates that upon excitation the radical anion of the PDI is formed with a rate of ca. 3.5 \times 109s-1, and the charge transfer state has a lifetime of ca. 3 ns. A Frontier Molecular Orbital description is provided, by using DFT calculations.

Abstract

The synthesis and photophysical properties of an asymmetrically substituted perylene-bis(dicarboximide), (PDI), system (1) containing a methylene bridged 4-methoxy-benzene donor and a solubilizing branched C13 alkyl chain are described. As compared to most PDIs, the fluorescence of 1 is strongly quenched in polar (but not in non-polar) solvents due to a photo-induced electron transfer process. Transient absorption spectroscopy and time resolved emission in e.g. acetonitrile indicates that upon excitation the radical anion of the PDI is formed with a rate of ca. 3.5 \times 109s-1, and the charge transfer state has a lifetime of ca. 3 ns. A Frontier Molecular Orbital description is provided, by using DFT calculations.

Anahtar kelimeler: Perylene dyes, photoconductivity, solar cells, LED, 3, 4, 9, 10-perylenetetracarboxylic diimide, excited state properties, photoinduced electron transfer, transient absorption, time resolved emission