Quantification of distortion of the water OH-band using picosecond Raman spectroscopy

An anomalously large (~40 cm −1 ) blue-shift of the Raman OH stretching vibration band was observed when bulk water was probed by picosecond versus nanosecond pulses. The temperature distortion of the OH band contour (3200–3600 cm −1 ) was studied by both nanosecond and picosecond Raman techniques. It was observed that the OH band centroid shifted linearly with temperature (~0.87 cm −1 °C −1 ) for both nano- and picosecond pulses. This feature of the picosecond Raman spectra was explained by the dynamics of the non-equilibrium hydrogen bond structures in water.