Relation between rotational and translational dynamic heterogeneities in water.
We use molecular dynamics simulations to probe the rotational dynamics of the extended simple point charge model of water for a range of temperatures down to 200 K, 6 K above the mode coupling temperature. We find that rotational dynamics is spatially heterogeneous; i.e., there are clusters of molecules that rotate significantly more than the average for a given time interval, and we study the size and the temporal behavior of these clusters. We find that the position of a rotational heterogeneity is strongly correlated with the position of a translational heterogeneity, and that the fraction of molecules belonging to both kinds of heterogeneities increases with decreasing temperature. We further find that although the two types of heterogeneities are not identical, they are related to the same physical picture.
Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215, USA.
Marco G
MG
Mazza
Nicolas
N
Giovambattista
Francis W
FW
Starr
H Eugene
HE
Stanley
D003198:Computer Simulation; D008956:Models, Chemical; D013696:Temperature; D014867:Water / Q000737:chemistry*
D014867:Water