posted on 2014-04-24, 00:00authored byDonghwa Lee, Eric Schwegler, Yosuke Kanai
First-principles
molecular dynamics simulations are used to gain
an atomistic-level insight into how the molecular behavior of interfacial
water is influenced by specific surface adsorbates. Although the overall
hydrophobic versus hydrophilic character of a given surface is widely
recognized to be important in determining the behavior of interfacial
water molecules, we show that subtle molecular details may also play
a role in determining the dynamical behavior of water. By comparing
water diffusivity at three different nonpolar surfaces, we find that
specific surface features can lead to a suppression of hydrogen bond
network ring structures by enhancing hexagonal spatial distributions
of water molecules near the surface. Such a distinct molecule-dependent
behavior of the interfacial water was found to persist well into the
liquid, while most structural properties are noticeably influenced
in only the first water layer.