Local Bonding Analysis of the Valence and Conduction Band Features of TiO2

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2764004· OSTI ID:930526

Fleming, L; Fulton, C; Lucovsky, G; Rowe, J; Ulrich, M; Luning, J

An analysis of the valence and conduction band electronic structure of TiO{sub 2} as studied by ultraviolet photoemission spectroscopy (UPS) and x-ray absorption spectroscopy (XAS) using synchrotron radiation is reported. Valence band spectra from UPS have been deconvolved using a five-peak model. The spectra are interpreted based on the peak assignments to the XAS data and the symmetries of the valence band states. The interpretation is consistent with theoretical calculations of molecular orbitals found in the literature. The removal of the d-state degeneracies that arise from a collective Jahn-Teller splitting of the crystal field split t{sub 2g} and e{sub g} states is observed and scales with the conduction band results from the absorption data. These Jahn-Teller derived energy separations are present in the O K{sub 1} and Ti L{sub 3} spectra but are not resolved in the photoemission valence band spectra. Two defect states are clearly observed {approx}0.7 and 2.0 eV above the valence band edge and are attributed to the presence of oxygen atom vacancies that are described in terms of Ti{sup 3+} states.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 930526
• Report Number(s): BNL--80551-2008-JA
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Vol. 102; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ABSORPTION
ABSORPTION SPECTROSCOPY
ATOMS
BINDING ENERGY
CRYSTAL FIELD
DEFECTS
ELECTRONIC STRUCTURE
OXYGEN
PHOTOEMISSION
SPECTRA
SPECTROSCOPY
SYNCHROTRON RADIATION
TITANIUM OXIDES
VACANCIES
VALENCE
X-RAY SPECTROSCOPY
national synchrotron light source