Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5417317 | Journal of Molecular Structure: THEOCHEM | 2009 | 6 Pages |
Abstract
The DFT-B3LYP method has been used for the ground-state (S0) geometry optimization of two novel compounds, 2-dicyanovinyldithieno[2,3-b:3â²,2â²-d]thiophene (DCST) and 2-dicyanovinyldithieno[3,2-b:2â²,3â²-d]thiophene (DCTT). The CASSCF approach has also been used to optimize the S0 and S1 electronic states of their more stable isomers, DCST 1 and DCTT 2. The absorption spectra of DCST and DCTT have been investigated at the TD-B3LYP/cc-pVTZ level, compared with the experimental results in the hexane solution. The studies indicate that the two notable absorption bands of DCST 1 occur at 387.83 and 265.04Â nm, respectively, which agree very well with the experimental data of 404 and 270Â nm, respectively; the two major absorption peaks of DCTT 2 appear at 403.42 and 257.84Â nm, respectively, also in good agreement with the observed values of 427 and 256Â nm, respectively. In addition, the emission wavelengths of DCST 1 and DCTT 2, under the S1 geometries, are 454.17 and 470.79Â nm, respectively, showing the remarkable red-shift in comparison with the corresponding absorption wavelengths.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
Xugeng Guo, Lei Zhu, Chaojie Li, Hua Wang, Jinglai Zhang,