Journal of Chemical Physics, Vol.110, No.12, 5814-5820, 1999
Transient spectral hole burning and hydrogen-bond breaking determined in different solutions of ethanol in deuterated ethanol
We present data on time-resolved infrared spectroscopy of ethanol diluted in deuterated ethanol at two concentrations of 1 and 50 vol % and excitation within the OH-stretching band. Transient spectral holes with widths of 35-55 cm(-1) and 25 cm(-1), respectively, are determined as well as breaking of hydrogen bonds after vibrational excitation. The lifetime of the OH mode of associated ethanol depends on the strength of the H bond and varies between <1 ps and 1.5+/-0.5 ps. While at the lower concentration the thermal effect due to the deposited energy is negligible, the higher concentration results in a pronounced heating of the excited molecules. Two different relaxation mechanisms of the excited OH mode of associated ethanol are discussed.