Raman excitation profiles and excited state molecular configurations of three isomeric acetylpyridines and acetophenone

Contributions of different electronic states to Raman scattering were studi ed by critical analyses of Raman excitation profiles (REPs) of several norm al modes of vibration of three isomeric acetyl pyridines and acetophenone. In this context, the possible structures and other interesting properties o f the four molecules in the excited electronic states were also discussed. Most Likely a singlet state, lying in the vacuum ultraviolet region with re spect to the ground state, is found to play a very significant role in the scattering phenomena, (C) 2000 Academic Press.