Abstract: The Lennard-Jones potential and Barker-Henderson perturbationtheory are used to calculate the dispersion and repulsion energies between molecules. The dipole-dipole energy for polar molecules is treated as an average of space orientation. The Helmholtz free energy contribution of dipole moment is deduced from the perturbation theory also and tested by Monte Carlo molecular simulation data. The dipole-induced dipole energy is considered too. The component activity coefficients for H2O-nC4H9OH binary system are calculated. The results are satisfactory.

摘要： 本文对流体分子中的色散能和排斥能采用Lennard-Jones位能函数和Barker-Henderson微扰理论进行计算;偶极定向能采用空间取向平均和微扰理论处理,并用Monte Carlo分子模拟数据进行了验证;还考虑了诱导偶极能.在此基础上,计算了H_2O-nC_4H_9HO二元体系液相组分活度系数,结果满意.