Partition coefficient of Polychlorinated biphenyls (PCBs) is important property for environment governance. We employed the all-atom molecular dynamics (MD) simulation to calculate solvation free energies of the PCBs in water and 1-octanol, respectively. The solvation free energy was predicted using thermodynamics integration (TI) approach. Two methods were compared to calculate the integrations of free energy in the TI approach. To improve the accuracy of our calculations, optimized atomic partial charges were applied for the PCBs in our MD simulations, leading to good computational predictions in partition coefficients. Our computational studies provided reliable data for separation process design.

多氯联苯（PCB）的分配系数是环境治理的重要属性。我们采用全原子分子动力学（MD）模拟来分别计算PCB在水和1-辛醇中的溶剂化自由能。使用热力学积分（TI）方法预测了溶剂化自由能。在TI方法中，比较了两种方法以计算自由能的积分。为了提高我们的计算精度，我们在MD模拟中将优化的原子部分电荷应用于PCB，从而在分配系数方面取得了良好的计算预测。我们的计算研究为分离过程设计提供了可靠的数据。