TORSIONAL SPLITTING OF THE INTERMOLECULAR VIBRATIONS OF PHENOL (H2O)(1) AND ITS DEUTERATED ISOTOPOMERS

The intermolecular vibrations of phenol-water and their tunneling (tor sional) splittings have been assigned in the S-1 state by mass resolve d spectral hole burning. The abundance of transitions in the low frequ ency region of the spectra can be traced back to torsional tunneling o f the water moiety, which splits all vibronic levels, Especially the i n plane wag vibration beta(2) exhibits a large splitting which points to a strong coupling with the H2O torsion tau and a substantial loweri ng of the effective torsional barrier after beta(2) excitation. Based on the discrimination of different isotopomers and their isomers and o f the torsional sublevels a reassignment of some intermolecular transi tions could be given. (C) 1998 American Institute of Physics.