Ions, OH (H2O)(n), were produced from a liquid beam of pure water by irradiation of a Mid- and a Near-IR lasers resonant to the fundamental and the forth harmonic of the OH vibration of the liquid water, respectively. The ions were composed of two components originating from the liquid beam surface and the inside, which liberated the ions into the gas phase at 0.2 and 1.7 +/- 0.2 mu s, respectively, after the Near-IR excitation. The Near-IR excitation created an ion pair (H+ center dot center dot center dot OH) in the course of non-equilibrium disintegration of the liquid beam induced by the Mid-IR excitation. (c) 2008 Elsevier B.V. All rights reserved.