求解简单液体径向分布函数的微扰方法

给出了求解简单液体径向分布函数的微扰方法,该方法把分子间相互作用势分解成参考势与微扰势之和,把径向分布函数、全相关函数、直接相关函数及桥函数表示成微扰级数的形式,假设零级桥函数为已经的参考流体的桥函数,其余级次的桥函数都为零,得到了各级函数所满足的积分方程和闭包关系.利用上述方法分别计算了单元和二元硬核Lenard-Jones流体的径向分布函数,并与用Choudhury理论计算的结果进行了比较,计算结果验证了本文方法的正确性.

A NEW PERTURBATION METHOD FOR CALCULATING PAIR CORRELATION FUNCTION OF SIMPLE LIQUIDS AND THEIR MIXTURE

This paper proposes a new perturbation method for calculating pair correlation function of simple liquids and their mixture.The interaction potential between a pair of molecules is divided into reference potential and perturbative contribution.Functions such as the pair correlation function,total correlation function,direct correlation function as well as bridge function are expressed in the form of series expansion.Integral equations and closure relations for calculating every grade of pair correlation function are obtained.The bridge function series is supposed to only have one term which is exact for reference fluid.Tests on hard core Lenard-Jones fluids and their mixture are carried out to demonstrate the new formulas.The pair correlation functions are calculated by both perturbation method and O-Z equations combining Choudhury8] bridge function approximation.The good agreement of the results beween both of the methods proves the validity of the new perturbation method.