State Key Laboratory of Molecular Reaction Dynamics , Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023 , China.
University of the Chinese Academy of Sciences , Beijing 100039 , China.
J Phys Chem A. 2019 Sep 12;123(36):7847-7854. doi: 10.1021/acs.jpca.9b02055. Epub 2019 Sep 3.
Morse function is suggested to be more suitable for studying the gas adsorption in porous frameworks than the Lennard-Jones and exponential-6 forms. However, there have not been some widely used Morse-based van der Waals force fields (vdW FFs) because of complicated parameterization. Combining rules is usually suggested to reduce the parameterization by calculating the unlike-pair parameters from the information of the like pair. A new set of combination rules (DRS) for Morse-based FF has been proposed in our prior work and shown good performance in the simulation of CH adsorption isotherms in covalent organic frameworks. Inspired by our prior work, we developed an accurate van der Waals FF using high-level ab initio calculations with the DRS combination rules. The validation was conducted by comparing the simulated gas uptakes with the experimental values for various known porous materials. The agreement between simulations and experiments is very good, showing the potential application of the FF and the DRS combination rules.
莫尔斯函数被认为比 Lennard-Jones 和指数-6 形式更适合研究多孔骨架中的气体吸附。然而，由于参数化复杂，还没有一些广泛使用的基于莫尔斯的范德华力场（vdWFF）。组合规则通常被建议用来通过从相似对的信息计算不相似对的参数来减少参数化。在我们之前的工作中，提出了一种新的基于莫尔斯的 FF 的组合规则（DRS），并在共价有机骨架中 CH 吸附等温线的模拟中表现出良好的性能。受我们之前工作的启发，我们使用基于 DRS 组合规则的高精度从头计算方法开发了一种准确的范德华力场 FF。通过将各种已知多孔材料的模拟气体吸收量与实验值进行比较来进行验证。模拟与实验之间的一致性非常好，表明了 FF 和 DRS 组合规则的潜在应用。
