RIKEN Research Center for Computational Science, Kobe, Hyogo, 650-0047, Japan.
Graduate School of Nanobioscience, Yokohama City University, Yokohama-City, Kanagawa, 236-0027, Japan.
J Comput Chem. 2019 Jan 5;40(1):172-180. doi: 10.1002/jcc.25562. Epub 2018 Oct 9.
We apply ab initio path integral molecular dynamics simulation employing ωB97XD as the quantum chemical calculation method to acetic acid-arsenic acid anion and acetic acid-phosphoric acid anion clusters to investigate the difference of the hydrogen bond structure and its fluctuation such as proton transfer. We found that the nuclear quantum effect enhanced the fluctuation of the hydrogen bond structure and proton transfer, which shows treatment of the nuclear quantum effect was essential to investigate these systems. The hydrogen bond in acetic acid-arsenic acid anion cluster showed characters related to low-barrier hydrogen bonds, while acetic acid-phosphoric acid anion cluster did not. We found non-negligible distinction between these two systems, which could not be found in conventional calculations. We suggest that the difference in amount of atomic charge of the atoms consisting the hydrogen bond is the origin of the difference between acetic acid-arsenic acid and acetic acid-phosphoric acid anion cluster. © 2018 Wiley Periodicals, Inc.
我们采用从头算路径积分分子动力学模拟，使用 ωB97XD 作为量子化学计算方法，对乙酸-砷酸阴离子和乙酸-磷酸阴离子簇进行研究，以考察氢键结构及其波动（如质子转移）的差异。我们发现，核量子效应对氢键结构和质子转移的波动有增强作用，这表明处理核量子效应对研究这些体系是必要的。在乙酸-砷酸阴离子簇中的氢键表现出与低势垒氢键相关的特征，而在乙酸-磷酸阴离子簇中则没有。我们发现这两个体系之间存在不可忽视的差异，这在传统计算中是无法发现的。我们认为，构成氢键的原子的原子电荷数量的差异是乙酸-砷酸和乙酸-磷酸阴离子簇之间差异的起源。© 2018 年 Wiley Periodicals, Inc.
