Planar Intramolecular Charge Transfer Precursor Mechanism

3 Planar Intramolecular Charge Transfer Precursor Mechanism 

According to the authors, the poor charge redistribution (delocalization) ability is responsible for the unfavorable TICT-forming process and facilitates the competition of the single-bond torsional reaction. In contrast, the quinoidal character of a molecule in the PICT state kinetically favors both fluorescence and photoisomerization but disfavors the single-bond torsion. The concept of thermodynamically allowed, but kinetically inhibited, TICT formation was formulated. 

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