Ultrafast vibrational energy transfer from O–H stretching modes of liquid water

Vibrational energy transfer from the O–H stretching modes in liquid water is studied by using QM/MM simulations and principal mode analysis (PMA). Two energy relaxation time scales of 0.6–0.7 and 0.3 ps are obtained by decorrelating the vibrational energy into principal modes. The longer time is interpreted as a vibrational energy relaxation (VER) process from the solute to bath, while the shorter time scale is attributed to an intramolecular vibrational energy redistribution (IVR) between the two O–H stretching modes.