Extent of inter-hydrogen bond correlations in water. Temperature effect

In a series of molecular dynamics calculations, we analyze static and dynamic correlations with fluctuations of neighboring bonds in water above and below room temperature, including the supercooled regime. For molecular pairs sharing a common hydrogen bond, we find that the probabilities of participating in additional bonds are well described as statistically uncorrelated events. Through an application of the reactive-flux formalism, we partition the dynamics according to the local environment of hydrogen bonding. We show that the variation of relaxation rate with respect to changes in local hydrogen bond population has little dynamical consequences at all temperatures studied. Furthermore, we discuss the experimental evidence for both findings. (C) 2000 Published by Elsevier Science B.V. All rights reserved.