Temperature dependence of quantum effects in liquid water.

Quantum and classical simulations are carried out on model water systems over a wide range of temperatures, from 100 to -35 degrees C. A detailed examination of the equilibrium and dynamical properties of liquid water is presented, together with a discussion of the interplay between quantum mechanical tunneling and dynamics. The study shows that quantum effects are essential for a description of the dynamical behavior of liquid water, particularly in the low-temperature (supercooled) region. The similarities and differences between quantum effects and the effects associated with increasing the temperature are explicitly characterized.