Resonance Raman spectroscopy and theoretical study on the photodissociation dynamics of formanilide in S3 state

Abstract

AbstractResonance Raman spectra were obtained for formanilide (FA) in acetonitrile solution with 239.5‐ and 245.9‐nm excitation wavelengths in resonance with the S3 state, and density functional theory (DFT) was used to elucidate the electronic transitions and resonance Raman spectra of FA. The spectra indicate that, in the Franck–Condon region, photodissociation dynamics has a multidimensional character with the motions mainly along the CO stretching υ8, the ring CC stretch υ9, the NH wag and ring CCH in‐plane bend υ11, the NH wag and ring CCH in‐plane bend υ12, ring CC stretch and ring CCH in‐plane bend υ16, the NH wag and ring CCH in‐plane bend υ17, the ring CCH in‐plane bend υ18, and the ring trigonal bend υ24. The excited‐state dynamics of the S3 state is discussed, and the results are compared with those previously reported for benzamide (BA) to examine the N‐ or C‐terminal‐substituted aromatic effect of the peptide bond. Copyright © 2010 John Wiley & Sons, Ltd.