Abstract

We present the results of calculations that have been performed to simulate the adsorption and diffusion of several model molecules, consisting of two carboxylic acid binding groups connected to a molecular backbone, on the TiO2 (110) rutile surface in order to investigate the effect of molecular structure on their surface mobility. The calculations were performed using a set of interatomic potentials that have been specifically developed to correctly reproduce the molecule-surface interaction for this system, along with established potentials for the isolated surface and intramolecular interactions. These potentials were tested through a comparison of adsorption energies and diffusion barriers of prototype molecules. We show that the rigidity of the molecular structure can significantly affect both the adsorption energy and the energy barriers for diffusion on the surface. As a result of the simulations we suggest a rigid molecular structure that will maximize the diffusion barrier. Calculations such as these will enable the design of molecules in order to tailor their diffusive properties for specific applications. © 2008 American Chemical Society.