体相CO2约化自扩散系数的标度律关联模型

用巨正则转换矩阵蒙特卡罗（GC-TMMC）和分子动力学（MD）模拟方法研究了体相CO2单位分子的过剩熵与其约化自扩散系数（D*s）的标度关系。过剩熵主要考虑3种定义：总体过剩熵sex，以分子重心径向分布函数定义的二体熵s(2)c和所有原子径向分布函数定义的二体熵s(2)t。结果表明，总体过剩熵sex与D*s之间存在明显的标度关系，并且独立于状态点所处的相态，可以用热力学量-过剩熵来关联动力学量-自扩散系数（约化方式）；二体熵在小于超临界温度范围内的标度结果偏离了-sex-D*s的“共同曲线”。本文拓展了过剩熵标度律在分子流体中的应用范围，得到了其在体相CO2自扩散系数关联中的应用规律。

On the use of excess entropy scalinglaws to describe the reduced self-diffusivities of bulk CO2

We have used molecular simulations to investigate the connection between self-diffusivity and the excess entropy of CO2.In this work,we consider three versions of the excess entropy.The first is the total thermodynamic excess entropy sex,which accounts for all intermolecular(two-,three-,and higher-body) correlations.The other two are the two-body contributions to the excess entropy obtained from the pair-correlation function of the fluid,which can be defined either from center of mass positional correlations(s(2)c) or from atom-atom pair correlation functions(s(2)t).We find that all the thermodynamic excess entropies serve as a suitable metric for describing the reduced transport properties over a broad range of state conditions.Interestingly,for the reduced self-diffusivity(D*s),a stronger connection between D*s and sex,and a comparatively weaker connection between D*s and s(2)c and s(2)t was observed over a broad range of state conditions.