NS  Vol.5 No.2 , February 2013
Fluid phases of argon: A debate on the absence of van der Waals’ “critical point”
ABSTRACT

A phase diagram of argon based upon percolation transition loci determined from literature experimental p-V isotherms, and simulation values using a Lennard-Jones model shows three fluid phases. The liquid phase spans all temperatures, from a metastable amorphous ground state at 0K, to ultra-high T. There is a supercritical mesophase bounded by percolation transition loci, and a gas phase. Intersection of two percolation loci in the p-T plane thermodynamically defines a critical line between two coexisting gas and liquid critical states at T = Tc, and the single mesophase for T > Tc. A debate on the absence of a van der Waals critical point in the Gibbs p-T density surface is appended.


Cite this paper
Woodcock, L. (2013) Fluid phases of argon: A debate on the absence of van der Waals’ “critical point”. Natural Science, 5, 194-206. doi: 10.4236/ns.2013.52030.
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