Orea P, Romero-Martínez A, Basurto E, Vargas C A, Odriozola G
Instituto Mexicano del Petróleo, Dirección de Investigación en Transformación de Hidrocarburos, Eje Central Lázaro Cárdenas 152, 07730 México D.F., Mexico.
Instituto Mexicano del Petróleo, Dirección de Investigación en Exploración y Producción, Eje Central Lázaro Cárdenas 152, 07730 México D.F., Mexico.
J Chem Phys. 2015 Jul 14;143(2):024504. doi: 10.1063/1.4926464.
It was recently shown that vapor-liquid coexistence densities derived from Mie and Yukawa models collapse to define a single master curve when represented against the difference between the reduced second virial coefficient at the corresponding temperature and that at the critical point. In this work, we further test this proposal for another generalization of the Lennard-Jones pair potential. This is carried out for vapor-liquid coexistence densities, surface tension, and vapor pressure, along a temperature window set below the critical point. For this purpose, we perform molecular dynamics simulations by varying the potential softness parameter to produce from very short to intermediate attractive ranges. We observed all properties to collapse and yield master curves. Moreover, the vapor-liquid curve is found to share the exact shape of the Mie and attractive Yukawa. Furthermore, the surface tension and the logarithm of the vapor pressure are linear functions of this difference of reduced second virial coefficients.
最近有研究表明,当以对应温度下的约化第二维里系数与临界点处的约化第二维里系数之差为横坐标时,米氏(Mie)模型和汤川(Yukawa)模型得出的气液共存密度会汇聚形成一条单一的主曲线。在这项工作中,我们针对伦纳德 - 琼斯(Lennard-Jones)对势的另一种推广形式进一步检验了这一观点。这是在低于临界点的一个温度范围内,针对气液共存密度、表面张力和蒸气压进行的。为此,我们通过改变势软度参数进行分子动力学模拟,以产生从非常短到中等吸引力范围的情况。我们观察到所有性质都汇聚并产生了主曲线。此外,发现气液曲线与米氏模型和吸引性汤川模型的曲线形状完全相同。而且,表面张力和蒸气压的对数是这种约化第二维里系数之差的线性函数。