Low Energy Electron Diffraction Study of TiO₂(110)(2 × 1)-[HCOO]⁻

Abstract

The structure of an ordered (2 × 1) overlayer of [HCOO]− on rutile TiO2(110)(1 × 1) has been elucidated using quantitative low energy electron diffraction. Both the location of adsorbate atoms, and substrate relaxation are determined. In agreement with previous work, it is concluded that the formate moiety binds to the surface through both of its oxygens to two adjacent 5-fold surface titanium atoms, so that its molecular plane is aligned with the [001] azimuth, i.e., it lies parallel to the bridging oxygen rows. The local adsorption geometry is in excellent quantitative agreement with that derived in a recent photoelectron diffraction study (Sayago, D. I.; et al. J. Phys. Chem. B 2004, 108, 14316).