We describe the application of the semiclassical Liouville method for simulating coherent quantum dynamics to the ultrafast dephasing of OH vibrational quantum coherence in liquid water. We simulate the decay of quantum coherence between the n = 0 and 1 vibrational states of the OH oscillator of dilute HOD in D2O using the approach. A novel quantum state dependent Hamiltonian based on the classical TIP3P potential of water is employed to allow quantum delocalization of the hydrogen atom in the OH bond to be treated. The vibrational dephasing time scale observed agrees qualitatively with recent experiments and molecular dynamics simulations. (C) 2011 Elsevier B. V. All rights reserved.