Interaction of liquid water with the rutile TiO₂ (110) surface

Abstract

A force-field which describes the interaction between the TiO₂ (110) rutile surface and a modified TIP3P water [P. Mark and L. Nilsson, J. Phys. Chem. A, 105, 9954, (2001)] is tested against periodic density functional theory (PDFT). Optimizations of water on the non-hydroxylated and hydroxylated surfaces are performed using PDFT and the geometries are compared with optimizations of modified TIP3P water on the TiO₂ surface using the force-field. The surface hydroxyl torsional profile is also compared using PDFT and force-field calculations as well as molecular dynamics (MD) simulations of the surface. MD simulations of liquid TIP3P water, containing dissolved Na⁺ and Cl⁻  ions, on six TiO₂ (110) surfaces at 298 K and 1 atm are performed for neutral surfaces and negatively-charged surfaces. Axial density and angular distributions show good agreement with results of Predota et al. [J. Phys. Chem. B, 108, 12049 (2004)] and X-ray crystal truncation rod experiments [Z. Zhang et al., Langmuir, 20, 4954 (2004)].

Keywords:

• Liquid water
• Rutile surface
• Periodic density functional theory
• Molecular dynamics simulations

Acknowledgements

The authors gratefully acknowledge the computer facilities of the Centre for Scientific Computing, University of Warwick. We thank the University of Warwick for the WPRF funding for A.S. Part of the funding also comes from the EPSRC Material Consortium “Modelling the Biological Interface with Materials”, GR/S80127/01.