流体熵相关性质的Monte Carlo模拟新方法

提出了用于计算实际体系熵相关性质的Monte Carlo多级取样分子模拟方法. 应用这一方法, 对硬球流体的化学势及Helmholtz自由能进行了估算, 得到了满意的结果. 计算化学势时, 不存在通常试验粒子方法所遇到的高密度问题. 该方法特别适合规律性的系统研究, 较之普通模拟方法要有效得多. 模拟得到的硬球体系无限稀释组份的超额化学势与对比直径的关系, 在相变区域为一条双凹曲线; 无论是在相变区还是在单相区, Carnahan-Starling公式对这一关系的描述均有较大偏差.

A New Simulation Approach to the Entropy-related Properties of Fluids

A new approach to the computation of entropy-related properties of fluid in a Monte Carlo molecular simulation is presented. Application of the new technique to hard sphere fluid shows that it is capable of providing reliable estimates of such properties as chemical potential and Helmholtz free energy, even at high density where other existed methods are difficult to apply. Moreover, the chemical potentials of an infinite dilute component in hard sphere systems are estimated and compared with that calculated from the Carnahan-starling equation.