Intramolecular vibrational energy re-distribution of water molecule induced by local-mode excitation

Intramolecular vibrational energy re-distribution (IVR) from local-mode excited states of water molecule is investigated on the basis of exact quantum mechanical wave packet propagation. The energy spectrum is calculated by Fourier transform of auto-correlation function. Progressions of local-mode exicted states are found in the energy range upto 5.5 eV. Wave functions of feature states of the local-mode character are obtained by use of the energy-filtration technique. Time evolution of those wave functions indicates that the vibrational energy of one bond-stretching is transmitted to the bending motion in several tens femtoseconds. The energy transfer to the other bond-stretching takes more than 1 ps.