Kerr Matthew, Ackland Graeme J, Marenduzzo Davide, Brandani Giovanni B, Pruteanu Ciprian G
SUPA, School of Physics and Astronomy and Centre for Science at Extreme Conditions, The University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom.
Department of Biophysics, Division of Biology, University of Kyoto, Kyoto 6068502, Japan.
J Chem Phys. 2024 Aug 7;161(5). doi: 10.1063/5.0211222.
We have performed classical molecular dynamics simulations using the fully polarizable Atomic Multipole Optimized Energetics for Biomolecular Applications (AMOEBA) forcefield implemented within the Tinker package to determine whether a more adequate treatment of electrostatics is sufficient to correctly describe the mixing of methane with water under high pressure conditions. We found a significant difference between the ability of AMOEBA and other classical, computationally cheaper forcefields, such as TIP3P, simple point charge-extended, TIP4P, and optimized potentials for liquid simulations-all atom. While the latter models fail to detect any effect of pressure on the miscibility of methane in water, AMOEBA qualitatively captures the experimental observation of the increased solubility of methane in water with pressure. At higher temperatures, the solubility of water in methane also increases; this seems to be associated with the breakdown of the fourfold hydrogen-bonded water network structure: bonding in water is weaker, so the energy cost of solution is lowered.
我们使用Tinker软件包中实现的全极化生物分子应用原子多极优化能量学（AMOEBA）力场进行了经典分子动力学模拟，以确定对静电作用进行更适当的处理是否足以正确描述高压条件下甲烷与水的混合情况。我们发现，AMOEBA与其他经典的、计算成本较低的力场（如TIP3P、简单点电荷扩展、TIP4P以及液体模拟全原子优化势）的能力存在显著差异。虽然后者模型未能检测到压力对甲烷在水中混溶性的任何影响，但AMOEBA定性地捕捉到了甲烷在水中的溶解度随压力增加的实验观察结果。在较高温度下，水在甲烷中的溶解度也会增加；这似乎与四重氢键水网络结构的破坏有关：水中的键合较弱，因此溶液的能量成本降低。
