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Three-Particle Correlations in Simple Liquids

Klaus Zahn·Georg Maret·Carsten Russ·Hans Hennig von Grunberg
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Abstract

We use video microscopy to follow the phase-space trajectory of a two-dimensional colloidal model liquid and calculate three-point correlation functions from the measured particle configurations. Approaching the fluid-solid transition by increasing the strength of the pair-interaction potential, one observes the gradual formation of a crystal-like local order due to triplet correlations, while being still deep inside the fluid phase. Furthermore, we show that in a strongly interacting system the Born-Green equation can be satisfied only with the full triplet correlation function but not with three-body distribution functions obtained from superposing pair-correlations (Kirkwood superposition approximation).

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Klaus Zahn, Georg Maret, Carsten Russ, Hans Hennig von Grunberg. 2003-07-18. Three-Particle Correlations in Simple Liquids. https://doi.org/10.1103/physrevlett.91.115502

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