Department of Chemistry and Physics, Indiana State University, Terre Haute, Indiana 47809, United States.
J Phys Chem A. 2023 Feb 23;127(7):1628-1635. doi: 10.1021/acs.jpca.3c00047. Epub 2023 Feb 13.
A method of unifying the equilibrium thermodynamic properties Δ and Δ relating to the van der Waals dimers and trimers of 15 nonpolar gases (He-Xe, H, D, CH, CF, ethene, ethane, CO, SF, propane, and neopentane) is described. Values of Δ and Δ, obtained at the reduced temperature = 0.7, show good correlation with the respective Lennard-Jones pair potential well depth, calculated from the monomer critical temperature and the acentric factor. Such relationships present the opportunity to estimate the van der Waals dimer and trimer thermodynamic properties of other nonpolar molecules, and examples of seven such applications are given. It is found that the enthalpies of dimerization and trimerization of the 15 gases are about 21 and 29% of the respective condensation enthalpies, providing information about the thermodynamics of small clusters in relation to liquefaction.
描述了一种将与 15 种非极性气体（He-Xe、H、D、CH、CF、乙烯、乙烷、CO、SF、丙烷和新戊烷）的范德华二聚体和三聚体相关的平衡热力学性质 Δ 和 Δ 统一的方法。在约化温度 = 0.7 下获得的 Δ 和 Δ 值与各自的 Lennard-Jones 对势能阱深度具有良好的相关性，该势能阱深度是从单体临界温度和偏心因子计算得出的。这种关系为估计其他非极性分子的范德华二聚体和三聚体热力学性质提供了机会，给出了七个此类应用的示例。结果发现，这 15 种气体的二聚化和三聚化焓分别约为相应冷凝焓的 21%和 29%，这提供了有关小团簇与液化相关的热力学信息。
