Abstract: Vapor liquid equilibrium of aqueous solution of ［BMIM］Br in different temperature and pressure were simulated by NPT-Gibbs Ensemble Monte Carlo(GEMC) method with Towhee packages by using Linux system. A modifying dielectric constant method was proposed to calculate the long-range force. The results of modifying dielectric constant method, polarizable and nonpolarizable models were compared with experimental results. The results show that compared to the polarizable and nonpolarizable models, the modifying dielectric constant method has better accuracy. In addition, molecular dynamics simulation on ［BMIM］Br aqueous solution was carried out with DL_POLY packages using Linux system, the diffusion coefficients of ［BMIM］ ion, Br-ion and water were calculated. The results indicate that with the increase of water content in the solution, the diffusion coefficients of ILs’ions and water are significantly improved.

Key words: ionic liquid, molecular simulation, vapor liquid equilibrium, diffusion coefficient

摘要： 在Linux操作系统下采用Towhee软件和NPT-Gibbs系综Monte-Carlo方法（GEMC），模拟了不同温度、不同压力下二元体系［BMIM］Br+H₂O的汽液相平衡性质。提出了一种修正介电常数的方法来计算长程力，所得结果与非极化模型、极化模型及实验结果进行了比较。结果表明：相比于极化模型和非极化模型，修正介电常数的计算结果更接近实验值。此外，采用DL_POLY软件和分子动力学模拟的方法对［BMIM］Br水溶液的扩散系数进行了计算。结果表明：随着溶液中水含量的增多，ILs阴阳离子以及水分子的扩散系数得到了明显的改善。

关键词: 离子液体, 分子模拟, 汽液相平衡, 扩散系数