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arXiv · 1203.3892

Overdamped van Hove function of atomic liquids

Leticia López-Flores·Laura L. Yeomans-Reyna·Martín Chávez-Páez·Magdaleno Medina-Noyola
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Abstract

Using the generalized Langevin equation formalism and the process of contraction of the description we derive a general memory function equation for the thermal fluctuations of the local density of a simple atomic liquid. From the analysis of the long-time limit of this equation, a striking equivalence is suggested between the long-time dynamics of the atomic liquid and the dynamics of the corresponding \emph{Brownian} liquid. This dynamic equivalence is confirmed here by comparing molecular and Brownian dynamics simulations of the self-intermediate scattering function and the long-time self-diffusion coefficient for the hard-sphere liquid.

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Leticia López-Flores, Laura L. Yeomans-Reyna, Martín Chávez-Páez, Magdaleno Medina-Noyola. 2012-05-24. Overdamped van Hove function of atomic liquids. https://doi.org/10.1088/0953-8984%2F24%2F37%2F375107

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