Spectral Hole Burning and Evidence for Vibrational Energy Migration of H-Bonded Molecules Observed With Transient Infrared Spectroscopy

Via intense ps-excitation of the OH-stretching vibration of ethanol diluted in CCl₄ we succeed in spectral hole burning within the inhomogeneously broadened oligomer band. The lifetime of the transient hole and the v=1-level of the OH-stetch of associated ethanol molecules are determined to be about 1.2 and 1.7 ps, respectively. Further dynamical features are discussed which give evidence for energy migration within the H-bonded ethanol chains and subsequent breaking of the oligomers into shorter fragments.