UHV-Cleaved V2O3 (101¯2) by He I and He II UPS and XPS
V2O3 is a transition-metal oxide that exhibits a large metal-insulator transition at about 150 K. At room temperature, where these spectra were taken, it is metallic. Its metallic nature is evident both in the finite occupied density-of-states at the Fermi level, and in the double-peaked structure of the V 2p1/2 and 2p3/2 core-level peaks. The sample contains only V3+ cations, so the double-peaked structure does not arise from the presence of multiple valence states on the V cations. Caution must thus be exercised in interpreting cation 2p core-level spectra from such oxides. [See K. E. Smith and V. E. Henrich, Phys. Rev. B 50, 1382 (1994), for a discussion of the role of final-state screening in x-ray photoelectron spectroscopy core-level line shapes. See also R. L. Kurtz and V. E. Henrich, Surf. Sci. Spectra 5, 182 (1998).] The vanadium oxides exhibit a wide stoichiometry range (including Magneli phases); V2O3 is one the more stable lower oxides.
Publication Source (Journal or Book title)
Surface Science Spectra
Kurtz, R., & Henrich, V. (1998). UHV-Cleaved V2O3 (101¯2) by He I and He II UPS and XPS. Surface Science Spectra, 5 (3), 172-175. https://doi.org/10.1116/1.1247848