Femtosecond dynamics of intramolecular charge transfer in 4-dimethylamino-4′-cyanostilbene in polar solvents

doi:10.1016/0009-2614(96)00237-0

Chemical Physics Letters

Volume 253, Issues 1–2, 26 April 1996, Pages 69-76

https://doi.org/10.1016/0009-2614(96)00237-0 Get rights and content

Abstract

The femtosecond dynamics of 4-(N,N-dimethylamino)-4′-cyanostilbene (DCS) in acetonitrile and methanol solvent was studied by fluorescence upconversion and pump-probe absorption spectroscopy. The spectral evolution observed provides strong evidence for a fast internal charge-transfer (CT) process dominating the dynamics in the first few picoseconds, while Stokes shift dynamics seem to play only a minor role. The initially excited state seems to have already a large amount of CT character, in line with observations in jet-cooled DCS-solvent clusters. The non-exponential CT-state formation contains components significantly faster than longitudinal dielectric relaxation rates in the solvents studied, indicating a possible contribution by high-frequency vibrational modes.

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¹: Present address: Institut für Physikalische Chemie, Alexander-von-Humbolt Universität, Bunsenstr. 1, 10117 Berlin, Germany.

²: Present address: Institut für Physikalische Chemie und Elektrochemie, Universität Karlsruhe, Kaiserstr. 12, 76128 Karlsruhe, Germany.

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Femtosecond dynamics of intramolecular charge transfer in 4-dimethylamino-4′-cyanostilbene in polar solvents

Abstract

Chem. Phys.

Spectrochim. Acta

Chem. Phys. Letters

Chem. Phys. Letters

Chem. Phys. Letters

Chem. Phys. Letters

Chem. Phys. Letters

Chem. Phys. Letters

Chem. Phys. Letters

J. Chem. Phys.

Science

Ann. Rev. Phys. Chem.

Angew. Chem. Intern. Ed.

J. Chem. Phys.

J. Chem. Phys.

J. Phys. Chem.

J. Phys. Chem.