Laboratorio de Termodinámica, Departamento de Física, Universidad Autónoma Metropolitana, Iztapalapa, México DF, Mexico.
Phys Chem Chem Phys. 2012 Jan 28;14(4):1440-8. doi: 10.1039/c1cp22880c. Epub 2011 Dec 9.
In this work we study a set of soft-sphere systems characterised by a well-defined variation of their softness. These systems represent an extension of the repulsive Lennard-Jones potential widely used in statistical mechanics of fluids. This type of soft spheres is of interest because they represent quite accurately the effective intermolecular repulsion in fluid substances and also because they exhibit interesting properties. The thermodynamics of the soft-sphere fluids is obtained via an effective hard-sphere diameter approach that leads to a compact and accurate equation of state. The virial coefficients of soft spheres are shown to follow quite simple relationships that are incorporated into the equation of state. The approach followed exhibits the rescaling of the density that produces a unique equation for all systems and temperatures. The scaling is carried through to the level of the structure of the fluids.
在这项工作中，我们研究了一组具有明确柔软度变化的软球系统。这些系统是广泛应用于流体统计力学的排斥 Lennard-Jones 势的扩展。这种软球之所以有趣，是因为它们非常准确地代表了流体物质中有效的分子间排斥，而且还因为它们具有有趣的性质。软球流体的热力学是通过有效的硬球直径方法获得的，该方法导致了一个紧凑且精确的状态方程。软球的维里系数表现出相当简单的关系，这些关系被纳入状态方程中。所采用的方法展示了密度的缩放，为所有系统和温度产生了一个独特的方程。缩放一直延伸到流体结构的水平。
