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Fractional Stokes-Einstein and Debye-Stokes-Einstein relations in a network forming liquid

Stephen R. Becker·Peter H. Poole·Francis W. Starr
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Abstract

We study the breakdown of the Stokes-Einstein (SE) and Debye-Stokes-Einstein (DSE) relations for translational and rotational motion in a prototypical model of a network-forming liquid, the ST2 model of water. We find that the emergence of ``fractional'' SE and DSE relations at low temperature is ubiquitous in this system, with exponents that vary little over a range of distinct physical regimes. We also show that the same fractional SE relation is obeyed by both mobile and immobile dynamical heterogeneities of the liquid.

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Stephen R. Becker, Peter H. Poole, Francis W. Starr. 2006-05-07. Fractional Stokes-Einstein and Debye-Stokes-Einstein relations in a network forming liquid. https://doi.org/10.1103/physrevlett.97.055901

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