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Critical end point behaviour in a binary fluid mixture

Nigel B. Wilding
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Abstract

We consider the liquid-gas phase boundary in a binary fluid mixture near its critical end point. Using general scaling arguments we show that the diameter of the liquid-gas coexistence curve exhibits singular behaviour as the critical end point is approached. This prediction is tested by means of extensive Monte-Carlo simulations of a symmetrical Lennard-Jones binary mixture within the grand canonical ensemble. The simulation results show clear evidence for the proposed singularity, as well as confirming a previously predicted singularity in the coexistence chemical potential [Fisher and Upton, Phys. Rev. Lett. 65, 2402 (1990)]. The results suggest that the observed singularities, particularly that in the coexistence diameter, should also be detectable experimentally.

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Nigel B. Wilding. 1997-04-11. Critical end point behaviour in a binary fluid mixture. https://doi.org/10.1103/physreve.55.6624

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