Fluid phases of argon: A debate on the absence of van der Waals’ “critical point”

• 作者: Leslie V. Woodcock
• 来源期刊: 自然科学期刊(英文)
• 学科: 化学
• 关键词: CRITICAL Point SUPERCRITICAL FLUIDS Liquid Phase
• 年，卷（期）: zrkxqkyw,（2）
• 页码范围: 194-206
• 页数: 13页
• 分类号: O6

摘要

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.