可变相互作用范围的方阱流体的液-气界面

Liquid-vapor interface of square-well fluids of variable interaction range.

作者信息

Orea Pedro, Duda Yurko, Weiss Volker C, Schröer Wolffram, Alejandre José

机构信息

Ingeniería Molecular, Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas 152, 07730 México D.F., México.

出版信息

J Chem Phys. 2004 Jun 22;120(24):11754-64. doi: 10.1063/1.1740749.

DOI:10.1063/1.1740749

PMID:15268210

Abstract

Properties of the liquid-vapor interface of square-well fluids with ranges of interaction lambda=1.5, 2.0, and 3.0 are obtained by Monte Carlo simulations and from square-gradient theories that combine the Carnahan-Starling equation of state for hard spheres with the second and third virial coefficients. The predicted surface tensions show good agreement with the simulation results for lambda=2 and for lambda=3 in a temperature range reasonably close to the critical point, 0.8</=T/T(c)</=0.95. As expected, the surface tension increases with the range of interaction and decreases monotonically with temperature. A comparison between theory and simulation results is also given for the width of the interface and for the coexistence curves for the different interaction ranges.

摘要

通过蒙特卡罗模拟以及结合硬球的卡纳汉 - 斯塔林状态方程与第二和第三维里系数的平方梯度理论，得到了相互作用范围λ = 1.5、2.0和3.0的方阱流体的液 - 气界面性质。在合理接近临界点的温度范围0.8≤T/T(c)≤0.95内，预测的表面张力与λ = 2和λ = 3时的模拟结果显示出良好的一致性。正如预期的那样，表面张力随着相互作用范围的增加而增大，并随温度单调降低。还给出了不同相互作用范围下界面宽度和共存曲线的理论与模拟结果的比较。