Ruiz-Barragan Sergi, Muñoz-Santiburcio Daniel, Körning Saskia, Marx Dominik
Lehrstuhl für Theoretische Chemie Ruhr-Universität Bochum, 44780 Bochum, Germany.
Phys Chem Chem Phys. 2020 May 20;22(19):10833-10837. doi: 10.1039/d0cp00916d.
Water presents puzzling properties once it gets confined down to the scale below about one nanometer, in particular its dielectric response becomes highly anisotropic in inhomogeneous environments such as slit pores. Here, we analyze the dielectric response of water within graphene slit pores in different confinement regimes based on molecular dynamics simulations. Our data quantify how the distinctly different parallel (in-plane) and perpendicular (out-of-plane) dielectric profiles change upon two-dimensional confinement from wide pores - featuring bulk-like behavior in between typical interfacial water layers - down to the water bilayer and monolayer limit. In addition, we show that simulating water in such narrow pores requires specific water-graphene interaction parameters different from those usually employed for interfaces.
一旦水被限制在约一纳米以下的尺度，它就会呈现出令人费解的特性，特别是在诸如狭缝孔隙等非均匀环境中，其介电响应会变得高度各向异性。在此，我们基于分子动力学模拟分析了不同限制条件下石墨烯狭缝孔隙内水的介电响应。我们的数据量化了在二维限制下，从具有典型界面水层间类似本体行为的宽孔隙，到水双层和单层极限，截然不同的平行（面内）和垂直（面外）介电分布是如何变化的。此外，我们表明，在如此狭窄的孔隙中模拟水需要特定的水 - 石墨烯相互作用参数，这些参数不同于通常用于界面的参数。
