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Mode-coupling theory of the stress-tensor autocorrelation function of a dense binary fluid mixture

Supurna Sinha·M. Cristina Marchetti
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Abstract

We present a generalized mode-coupling theory for a dense binary fluid mixture. The theory is used to calculate molecular-scale renormalizations to the stress-tensor autocorrelation function (STAF) and to the long-wavelength zero-frequency shear viscosity. As in the case of a dense simple fluid, we find that the STAF appears to decay as $t^{-3/2}$ over an intermediate range of time. The coefficient of this long-time tail is more than two orders of magnitude larger than that obtained from conventional mode-coupling theory. Our study focuses on the effect of compositional disorder on the decay of the STAF in a dense mixture.

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Supurna Sinha, M. Cristina Marchetti. 2006-05-03. Mode-coupling theory of the stress-tensor autocorrelation function of a dense binary fluid mixture. https://doi.org/10.1103/physreva.46.4942

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