Connection between Adam-Gibbs Theory and Spatially Heterogeneous Dynamics

TL;DR

This study explores the connection between the Adam-Gibbs theory and spatially heterogeneous dynamics in supercooled water, using molecular simulations to relate cluster size, diffusion, and entropy.

Contribution

It establishes a quantitative link between mobile particle cluster size and the Adam-Gibbs theory in supercooled liquids.

Findings

Cluster size correlates with diffusion constant.

Configurational entropy relates to cluster dynamics.

Transient clusters vary with time and temperature.

Abstract

We investigate the spatially heterogeneous dynamics in the SPC/E model of water by using molecular dynamics simulations. We relate the average mass $n^*$ of mobile particle clusters to the diffusion constant and the configurational entropy. Hence, $n^*$ can be interpreted as the mass of the ``cooperatively rearranging regions'' that form the basis of the Adam-Gibbs theory of the dynamics of supercooled liquids. Finally, we examine the time and temperature dependence of these transient clusters.