1 research outputs found
Influence of Hydrogen Bonding on the Structure of the (001) Corundum–Water Interface. Density Functional Theory Calculations and Monte Carlo Simulations
Density
functional theory calculations and classical Monte Carlo
simulations are applied to study the behavior of water in contact
with a hydroxylated corundum (001) surface. Using DFT with periodic
boundary conditions at <i>T</i> = 0 K, we systematically
study the influence of the number of water molecules on the surface
geometry and on the structure of the contact water layer. Only little
effect of the thickness of the water layer on the geometry of the
surface hydroxyl groups is observed. On the other hand, the molecules
in the second layer have strong influence on the arrangement of water
molecules in direct contact with the solid surface. In order to mimic
macroscopic systems at room temperature, we perform inhomogeneous
MC simulations of model corundum surface in contact with the water
phase modeled by SPC/E model. The water molecules are classified according
to their hydrogen-bonded partners into several groups. It is found
that the preferential orientation of interfacial water molecules is
primarily determined by the type of their hydrogen bonding. The hydroxyl
groups at the corundum surface can serve as hydrogen bond donor or
acceptor, depending on their orientation. No surface hydroxyls are
found to coordinate two water molecules at the same time. On the other
hand, water molecules coordinated by two different surface groups
appear in MC simulations