Structure and dynamics of water at the Pt(111) interface: Molecular dynamics study

Abstract

We prescribe an analytical form of the interaction potential between rigid water and a rigid platinum metal surface, which takes into account the surface symmetry and corrugation. Using this potential we perform a molecular dynamics computer simulation on water lamina restricted by two PtC 111) surfaces and investigate the structure and dynamics of water at the Pt interface. At 300 K the water layer adjacent to the metal surface displays solid-like properties. Patches of ice-like structure embedded in this layer are observed in the simulation. The next two layers of water display ordering similar to ice-I. Beyond these three layers the structure and dynamics of water are bulk-like.

Interplay of local hydrogen-bonding and long-ranged dipolar forces in simulations of confined water

“…The Pt(111) wall area was 3.05 nm × 2.88 nm with 1,054 SPC/E molecules, and the z c for the walls (as defined in ref. 33) were placed at ±1.56 nm. In both cases the simulation cell spanned 14.0 nm in the z direction, though this was only crucial for the Ewald summations to maintain sufficient vacuum space between periodically replicated slabs.…”

“…For this research, we have used the DLPOLY2.16 molecular dynamics package (37) modified to include the Lennard-Jones wall potential (25), the Pt(111) wall potential (33), the LMF theory v 0 (r) potential, and the V R (z) mean field potential, as well as the 3-dimensional corrected Ewald sum for slab systems (EW3DC) (38). SPC/E water (3) was simulated at constant volume and temperature by using the Berendsen thermostat (39) with a time step of 1 fs.…”

“…We now illustrate the application of LMF theory to moderately more realistic molecular surfaces by replacing the hydrophobic walls with empirical Pt(111) surfaces that order the water molecules at the surface, attracting the oxygen atoms to localized binding sites as shown by Berkowitz and coworkers (33). This surface is meant to represent specific interactions and detailed ordering of water molecules at an atomically corrugated surface, thus mimicking a hydrophilic interaction.…”

Integral equation theory for the electrode-electrolyte interface with the central force water model. Results for an aqueous solution of sodium chloride

“…ST2, TIP4P and SPC) have been employed mainly in computer simulations because of their complexity. Several authors have focused their attention on how the detailed atomic structure of the electrode affects the interfacial structure of pure water for instance through chemical bonding, surface corrugation [19,20] and image interactions modelling a metal electrode [21]. The model parameters are based on quantum mechanical ab initio calculations or on thermodynamic data.…”

Reactivity and Dynamics at Liquid Interfaces

“…223,[469][470][471][472][473][474][475] A few theoretical studies using molecular dynamics simulations have appeared. 228,[476][477][478][479] They were motivated by some conflicting reports about the ability of the interface region to enhance The reduced density at a liquid/vapor interface is expected to lower the collision frequency and to reduce the rate of rotational energy relaxation. At the same time, fewer collisions enable faster scrambling of molecular orientations and thus are expected to increase the rate of orientational relaxation (as long as the density is not too low 219 ).…”