Schlaich Alexander, Knapp Ernst W, Netz Roland R
Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.
Fachbereich Chemie, Freie Universität Berlin, Fabeckstraße 36a, 14195 Berlin, Germany.
Phys Rev Lett. 2016 Jul 22;117(4):048001. doi: 10.1103/PhysRevLett.117.048001. Epub 2016 Jul 19.
We investigate the dielectric profile of water confined between two planar polar walls using atomistic molecular dynamics simulations. For a water slab thickness below 1 nm the dielectric response is highly asymmetric: while the parallel component slightly increases compared to bulk, the perpendicular one decreases drastically due to anticorrelated polarization of neighboring water molecules. We demonstrate the importance of the dielectric contribution due to flexible polar headgroups and derive an effective dielectric tensorial box model suitable for coarse-grained electrostatic modeling.
我们使用原子分子动力学模拟研究了限制在两个平面极性壁之间的水的介电分布。对于厚度小于1纳米的水层，介电响应高度不对称：与本体相比，平行分量略有增加，而垂直分量由于相邻水分子的反相关极化而急剧下降。我们证明了由于柔性极性头基团引起的介电贡献的重要性，并推导了一个适用于粗粒度静电建模的有效介电张量盒模型。
