| Attributs | Valeurs |
|---|
| type
| |
| Is Part Of
| |
| Subject
| |
| Title
| - Intramolecular Charge-Transfer Mechanism in Quinolidines: The Role of the Amino Twist Angle
|
| has manifestation of work
| |
| related by
| |
| Author
| |
| Abstract
| - Quantum-chemical calculations with the approximate coupled-cluster singles-and-doubles modelCC2 have been carried out for 1-tert-butyl-6-cyano-1,2,3,4-tetrahydroquinoline (NTC6). For this moleculedual fluorescence was experimentally observed, raising the discussion about the importance of the aminotwist angle for this process. The calculations suggest that both the ground state and the normal fluorescentstate are significantly twisted by 30°−40° and that the molecule is flexible enough to move into an evenstronger twisted conformation (60°−70°) in its intramolecular charge-transfer (ICT) state which is responsiblefor the anomalous fluorescence band. Such a conformation both minimizes the total energy in the S1 stateand maximizes the dipole moment. The barrier from the normal fluorescent state to the ICT state region isvery small. Comparison to the situation in the 1-methyl-derivative NMC6 suggests that a large alkylsubstituent makes the preferably planar normal fluorescent state energetically unfavorable compared tothe ICT state and thus promotes the occurrence of dual fluorescence.
|
| article type
| |
| is part of this journal
| |
