Koperwas K, Grzybowski A, Paluch M
University of Silesia in Katowice, Institute of Physics, 75 Pułku Piechoty 1, 41-500 Chorzów, Poland and Silesian Center for Education and Interdisciplinary Research (SMCEBI), 75 Pułku Piechoty 1a, 41-500 Chorzów, Poland.
Phys Rev E. 2020 Jan;101(1-1):012613. doi: 10.1103/PhysRevE.101.012613.
In this paper, based on the molecular dynamics simulations of quasireal model systems, we propose a method for determination of the effective intermolecular potential for real materials. We show that in contrast to the simple liquids, the effective intermolecular potential for the studied systems depends on the thermodynamic conditions. Nevertheless, the previously established relationship for simple liquids between the exponent of the inverse power law approximation of intermolecular potential and the density-scaling exponent is still preserved when small enough intermolecular distances are considered. However, our studies show that molecules approach each other at these very short distances relatively rarely. Consequently, only sparse interactions between extremely close molecules determine the value of the scaling exponent and then strongly influence the connection between dynamics and thermodynamics of the whole system.
在本文中，基于准真实模型系统的分子动力学模拟，我们提出了一种确定真实材料有效分子间势的方法。我们表明，与简单液体不同，所研究系统的有效分子间势取决于热力学条件。然而，当考虑足够小的分子间距离时，先前建立的简单液体分子间势的逆幂律近似指数与密度标度指数之间的关系仍然成立。然而，我们的研究表明，分子在这些非常短的距离内相互靠近的情况相对较少。因此，只有极近距离分子间的稀疏相互作用决定标度指数的值，进而强烈影响整个系统动力学与热力学之间的联系。
