Picosecond time-resolved resonance Raman spectra of the A (intramolecular charge transfer, ICT) state of DMABN, DMABN-d6and DMABN-15N have been obtained. The isotopic shifts identify the vs(ph-N) mode as a band at 1281 cm-1. The ∼96 cm-1downshift of this mode from its ground state frequency rules out the electronic coupling PICT model and unequivocally supports the electronic decoupling TICT model. However, our results suggest some pyramidal character of the A state amino conformation.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry