Eskandari Nasrabad Afshin
Department of Physical Chemistry, School of Chemistry, University of Tehran, Tehran 14155-6455, Iran.
J Chem Phys. 2008 Dec 28;129(24):244504. doi: 10.1063/1.3046564.
An ab initio interaction potential available in literature is scaled via an empirical procedure and used in an extensive computer simulation study to investigate the thermodynamic properties and self-diffusion coefficient of krypton over a wide range of densities and temperatures. The thermodynamic properties of the fluid phase equilibriums are computed utilizing the Gibbs ensemble Monte Carlo simulation technique. The equation of state and the pair correlation function are obtained using the NVT-Monte Carlo simulation method. The time-correlation function formalism of Green-Kubo is applied in molecular dynamics simulations to calculate the self-diffusion coefficient. Furthermore, the modified Cohen-Turnbull theory is employed to determine the self-diffusion coefficient and the mean free volume needed for this purpose is provided via the generic van der Waals theory. The virial minimization method is used to compute the effective diameter and the results are applied within the generic van der Waals theory as the repulsion-attraction splitting distance of the interaction potential. A remarkable agreement is observed between the computed and empirical results for the orthobaric densities, the vapor pressure, the critical point, and the equation of state. A detailed analysis is presented for the calculated self-diffusion coefficient.
文献中可用的从头算相互作用势通过经验程序进行缩放,并用于广泛的计算机模拟研究,以研究氪在广泛的密度和温度范围内的热力学性质和自扩散系数。利用吉布斯系综蒙特卡罗模拟技术计算流体相平衡的热力学性质。使用NVT蒙特卡罗模拟方法获得状态方程和对关联函数。格林-库博的时间关联函数形式在分子动力学模拟中用于计算自扩散系数。此外,采用修正的科恩-特恩布尔理论来确定自扩散系数,并通过通用范德华理论提供为此所需的平均自由体积。维里最小化方法用于计算有效直径,其结果在通用范德华理论中用作相互作用势的排斥-吸引分裂距离。在正压密度、蒸气压、临界点和状态方程的计算结果与实验结果之间观察到了显著的一致性。对计算得到的自扩散系数进行了详细分析。