This contribution is in honor of Professor Keith E. Gubbins, an international leader in developing advances in statistical mechanics and molecular simulation for engineering applications. The research presented here extends the SAFT model that Chapman proposed and developed while a graduate student with Professor Gubbins. In this manuscript, a thermodynamic perturbation theory within a multi‐density formalism framework is extended to model species with a combination of monovalent and divalent association sites. Theory predictions are verified with Monte Carlo simulation results for different conditions of temperature, density, and angular size of the divalent site. The theory is applied to model water, where the two lone pairs of electrons on the oxygen atom are represented with a divalent site that includes cooperative hydrogen bonding. The theory results are in good agreement with experiments for saturated densities, vapor pressure, internal energy, and extent of hydrogen bonding.

中文翻译：

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结合物种上单价和二价位的组合：应用于水中

此贡献是对在开发用于工程应用的统计力学和分子模拟方面取得进展的国际领导者Keith E. Gubbins教授的荣誉。这里介绍的研究扩展了查普曼在古宾斯教授研究生期间提出并开发的SAFT模型。在此手稿中，在多密度形式主义框架内的热力学摄动理论被扩展到具有一价和二价缔合位点组合的模型物种。对于二价位的温度，密度和角大小的不同条件，通过蒙特卡洛模拟结果验证了理论预测。该理论适用于模拟水，其中氧原子上的两个孤对电子以包括合作氢键的二价位表示。