The interactions of a hydrophilic surface with water can significantly influence the characteristics of the liquid water interface. In this manuscript, we explore this influence by studying the molecular structure of liquid water at a disordered surface with tunable surface−water interactions. We combine all-atom molecular dynamics simulations with a mean field model of interfacial hydrogen bonding to analyze the effect of surface−water interactions on the structural and energetic properties of the liquid water interface. We find that the molecular structure of water at a weakly interacting (i.e., hydrophobic) surface is resistant to change unless the strength of surface−water interactions is above a certain threshold. We find that below this threshold water’s interfacial structure is homogeneous and insensitive to the details of the disordered surface, however, above this threshold water’s interfacial structure is heterogeneous. Despite this heterogeneity, we demonstrate that the equilibrium distribution of molecular orientations can be used to quantify the energetic component of the surface−water interactions that contribute specifically to modifying the interfacial hydrogen bonding network. We identify this specific energetic component as a new measure of hydrophilicity, which we refer to as the intrinsic hydropathy.

中文翻译：

---

水的界面氢键结构揭示了地表水相互作用的有效强度

亲水性表面与水的相互作用会显着影响液态水界面的特性。在本手稿中，我们通过研究具有可调地表水相互作用的无序表面上液态水的分子结构来探索这种影响。我们将全原子分子动力学模拟与界面氢键合的平均场模型相结合，以分析地表水相互作用对液态水界面的结构和能量特性的影响。我们发现弱相互作用的表面（即疏水性）表面的水分子结构具有抗变化性，除非地表水相互作用的强度高于某个阈值。我们发现，低于此阈值时，水的界面结构是均匀的，并且对无序表面的细节不敏感，但是，高于此阈值时，水的界面结构是不均匀的。尽管存在这种异质性，我们证明分子取向的平衡分布可用于量化地表水相互作用的高能成分，这特别有助于修饰界面氢键网络。我们将这种特定的能量成分确定为亲水性的一种新度量，我们将其称为固有亲水性。我们证明分子取向的平衡分布可用于量化地表水相互作用的高能成分，这特别有助于修改界面氢键网络。我们将这种特定的能量成分确定为亲水性的一种新度量，我们将其称为固有亲水性。我们证明分子取向的平衡分布可用于量化地表水相互作用的高能成分，这特别有助于修改界面氢键网络。我们将这种特定的能量成分确定为亲水性的一种新度量，我们将其称为固有亲水性。