Derivation of Force Field Parameters for TiO2−H2O Systems from ab Initio Calculations

Abstract

Periodic (CASTEP and DMol3) and cluster (Gaussian 98 and DMol3) ab initio calculations were carried out to develop force field parameters for the system Ti−O−H to model TiO2−H2O interfaces. A force field was derived from previously existing force fields for bulk TiO2 polymorphs (Matsui, M.; Akaogi, M. Mol. Simul. 1991, 6, 239) and water (SPC/E; Berendsen, H. J. C.; Grigera, J. R.; Straatsma, T. P. J. Phys. Chem. 1987, 91, 6269) that describes Ti in a variety of coordination environments, Ti−O−H bonding, and H-bonding on TiO2 surfaces. The force field was tested for its ability to reproduce ab initio structures of the hydrated (110) surface of α-TiO2 (rutile).