Geometric structure of (0 1 1)(21) surface by low energy electron diffraction (LEED)

A structural study has been performed on the TiO 2 (0 1 1)(2 × 1) surface by quantitative low energy electron diffraction (LEED), using a delay-line-detector (DLD–LEED) system. The atomic coordinates obtained are in good agreement with recent studies using surface X-ray diffraction (SXRD). The best-fit Pendry R factor is 0.29. This effectively rules out the other models previously proposed, which have significantly higher R factors. Despite the good agreement, however, a key feature of the bonding in this model, which has been suggested as the origin of the photo-catalytic activity of this surface, is not supported by the current analysis. Contrary to a previous study for the TiO 2 (1 1 0)(1 × 1) surface, it was also found that calculating the sample potentials self-consistently had little effect on the results.