Fedkin Mark V, Shin Yun Kyung, Dasgupta Nabankur, Yeon Jejoon, Zhang Weiwei, van Duin Diana, van Duin Adri C T, Mori Kento, Fujiwara Atsushi, Machida Masahiko, Nakamura Hiroki, Okumura Masahiko
Department of Mechanical and Nuclear Engineering , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States.
Department of Engineering Science and Mechanics , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States.
J Phys Chem A. 2019 Mar 14;123(10):2125-2141. doi: 10.1021/acs.jpca.8b10453. Epub 2019 Mar 1.
A new ReaxFF reactive force field has been developed for water-electrolyte systems including cations Li, Na, K, and Cs and anions F, Cl, and I. The reactive force field parameters have been trained against quantum mechanical (QM) calculations related to water binding energies, hydration energies and energies of proton transfer. The new force field has been validated by applying it to molecular dynamics (MD) simulations of the ionization of different electrolytes in water and comparison of the results with experimental observations and thermodynamics. Radial distribution functions (RDF) determined for most of the atom pairs (cation or anion with oxygen and hydrogen of water) show a good agreement with the RDF values obtained from DFT calculations. On the basis of the applied force field, the ReaxFF simulations have described the diffusion constants for water and electrolyte ions in alkali metal hydroxide and chloride salt solutions as a function of composition and electrolyte concentration. The obtained results open opportunities to advance ReaxFF methodology to a wide range of applications involving electrolyte ions and solutions.
一种新的ReaxFF反应力场已针对水 - 电解质系统开发出来，该系统包括阳离子Li、Na、K和Cs以及阴离子F、Cl和I。反应力场参数已根据与水结合能、水合能和质子转移能相关的量子力学（QM）计算进行了训练。通过将其应用于水中不同电解质电离的分子动力学（MD）模拟，并将结果与实验观察和热力学进行比较，对新的力场进行了验证。为大多数原子对（阳离子或阴离子与水的氧和氢）确定的径向分布函数（RDF）与从DFT计算获得的RDF值显示出良好的一致性。基于所应用的力场，ReaxFF模拟描述了碱金属氢氧化物和氯化物盐溶液中水和电解质离子的扩散常数与组成和电解质浓度的函数关系。所获得的结果为将ReaxFF方法推进到涉及电解质离子和溶液的广泛应用领域提供了机会。
