Entropy scaling close to criticality: From simple to metallic systems
Entropy scaling close to criticality: From simple to metallic systems
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熵缩放接近临界点：从简单系统到金属系统
DOI：
10.1103/physreve.103.052102
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发表时间：
2021
影响因子：
2.4
通讯作者：
Delhommelle, Jerome
中科院分区：
文献类型：
--
作者：
Desgranges, Caroline;Delhommelle, Jerome
熵最近引起了相当大的兴趣，既作为一个标记，以检测相变的开始，并作为一个反应坐标，或集体变量，跨越相变途径。在这里，我们专注于熵的行为沿着的汽-液相共存，并确定如何在熵的两个共存相之间的差异变化在理想和金属系统沿着的共存曲线。使用平面直方图模拟，我们确定共存的热力学条件，临界参数，包括临界熵，熵沿着的双结点。然后，我们将我们的分析应用到一系列的系统，越来越偏离理想，并通过逐步发病的弗里德尔振荡在一个有效的对电位，并为一系列过渡金属建模与多体嵌入原子力场。相边界在熵-压平面和熵-温平面上的投影表现出两种性质不同的行为。虽然所有的系统建模与有效的对潜在的理想的行为，多体效应的发病结果偏离理想和显着更大的指数的变化的熵的蒸发与温度远离临界温度。
Entropy has recently drawn considerable interest both as a marker to detect the onset of phase transitions and as a reaction coordinate, or collective variable, to span phase transition pathways. We focus here on the behavior of entropy along the vapor-liquid phase coexistence and identify how the difference in entropy between the two coexisting phases vary in ideal and metallic systems along the coexistence curve. Using flat-histogram simulations, we determine the thermodynamic conditions of coexistence, critical parameters, including the critical entropy, and entropies along the binodal. We then apply our analysis to a series of systems that increasingly depart from ideality and adopt a metal-like character, through the gradual onset of the Friedel oscillation in an effective pair potential, and for a series of transition metals modeled with a many-body embedded-atoms force field. Projections of the phase boundary on the entropy-pressure and entropy-temperature planes exhibit two qualitatively different behaviors. While all systems modeled with an effective pair potential lead to an ideal-like behavior, the onset of many-body effects results in a departure from ideality and a markedly greater exponent for the variation of the entropy of vaporization with temperature away from the critical temperature.