Prediction of thermodynamic properties for fluid nitrogen with molecular dynamics simulations
Prediction of thermodynamic properties for fluid nitrogen with molecular dynamics simulations
复制标题
通过分子动力学模拟预测液氮的热力学性质
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
J. Fischer
中科院分区：
文献类型：
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作者：
C. Kriebel;Andreas Müller;M. Mecke;Jochen Winkelmann;J. Fischer
本文报道了在等容等温系综中对液氮双中心Lennard-Jones模型的分子动力学模拟结果，该模型的特征为固定的分子伸长L = 1σ = 0.3292。通过对94，67 K下的实验数据拟合模型的蒸汽压和饱和液体密度，确定了新的ε和σ值。所需的汽液平衡数据的模型是从使用NpT +测试粒子方法的研究。得到的值是ε k = 36.32013 K（36.673 K）和σ = 0.32973 nm（0.33073 nm），括号中的值是以前从Weeks钱德勒安德森型微扰理论得到的值。然后通过分子模拟计算了温度范围为72 ~ 330 K、密度为35 mol ·L ~ 1的110个态点的压强和内能。新参数的基础上的预测与Jacobsen等人的经验状态方程的比较。除了在近临界区显示良好的协议。而且。对于几乎所有的状态点，新的参数都比来自微扰理论的旧参数有改进。
Molecular dynamics simulation results in the isochoric isothermal ensemble are reported for a two-center Lennard Jones model of fluid nitrogen characterized by the fixed molecular elongationL = 1σ = 0.3292, New values ofε andσ were determined by fitting the vapor pressure and the saturated liquid density of the model to experimental data at 94,67 K. The required vapor liquid equilibrium data of the model were taken from a study using the NpT + test particle method. The resulting values areε k = 36.32013 K (36.673 K) andσ = 0.32973 nm (0.33073 nm), with values in parentheses being those obtained previously from a Weeks Chandler Andersen-type perturbation theory. Then pressures and internal energies were calculated by molecular simulations for 110 state points in the temperature range from 72 to 330 K and for densities up to 35 mol · L1. Comparison of the predictions based on the new parameters with the empirical equation of state of Jacobsen et al. shows good to excellent agreement except in the near-critical region. Moreover. for almost all state points the new parameters yield an improvement over old ones from perturbation theory.