Resonance Raman study of ring deuterated 4-dimethylaminobenzonitrile (DMABN-d(4)): the ground, ICT and triplet states

Picosecond and nanosecond time-resolved resonance Raman spectra of the intr amolecular charge transfer (ICT) and triplet state of DMABN-d(4) have been obtained over the frequency range from 650 to 2250 cm(-1). The spectra and the isotopic shifts observed on going from normal DMABN to the ring deutera ted analogue are interpreted with the aid of DFT vibrational analysis of gr ound state spectra and comparisons made with closely related compounds. The data confirm our previous results but the isotopic shifts induced by the r ing deuteration provide additional evidence clarifying the planar structure of the triplet state and indicating full localisation of negative charge o n the cyano group. (C) 2001 Elsevier Science B.V. All rights reserved.