We present angle-resolved inverse-photoemission (IPE) spectroscopy data from the nearly perfect ${\mathrm{TiO}}_2$(110) surface. Results from two high-symmetry directions of the surface Brillouin zone, Γ¯-X¯ and Γ¯-X¯’, are reported and compared with the results of bulk and surface electronic-structure calculations. Features in the spectra appearing ∼1, 4, 9, and 13 eV above the Fermi level are associated with the primarily Ti-derived 2${\mathit{t}}_{2\mathit{g}}$, 3${\mathit{e}}_{\mathit{g}}$, 3${\mathit{a}}_{1\mathit{g}}$, and 4${\mathit{t}}_{1\mathit{u}}$ levels. The results are consistent with earlier studies using x-ray-absorption spectroscopy and electron-energy-loss spectroscopy but show some discrepancies in energy positions. All of the spectral features exhibit a small amount of dispersion with respect to ${\mathit{k}}_{\mathrm{\parallel }}$. Surface states and resonances identified in the 0–2-eV region are in accordance with previously published calculations [S. Munnix and M. Schmeits, Phys. Rev. B 30, 2202 (1984)]. The absence of surface resonances near 3 eV strongly suggests that the nearly perfect ${\mathrm{TiO}}_2$(110) surface is terminated by a bridging oxygen layer.

• Received 2 September 1992

DOI:https://doi.org/10.1103/PhysRevB.47.13722