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Independence of the relaxation of a supercooled fluid of its microscopic dynamics: need for yet another extension of the mode-coupling theory

Grzegorz Szamel·Elijah Flenner
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Abstract

Using Brownian Dynamics computer simulations we show that the relaxation of a supercooled Brownian system is qualitatively the same as that of a Newtonian system. In particular, near the so-called mode-coupling transition temperature, dynamic properties of the Brownian system exhibit the same deviations from power-law behavior as those of the Newtonian one. Thus, similar dynamical events cut off the idealized mode-coupling transition in Brownian and Newtonian systems. We discuss implications of this finding for extended mode-coupling theory. In addition, we point out and discuss the difference between our findings and experimental results, and present an alternative interpretation of some of our simulation data.

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Grzegorz Szamel, Elijah Flenner. 2004-07-20. Independence of the relaxation of a supercooled fluid of its microscopic dynamics: need for yet another extension of the mode-coupling theory. https://doi.org/10.1209/epl%2Fi2004-10117-6

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