We have measured high-energy-resolution Fe $2p$ photoelectron spectra for $\alpha -{\mathrm{Fe}}_2{\mathrm{O}}_3/\alpha -{\mathrm{Al}}_2{\mathrm{O}}_3\mathrm{}\left(0001\right)\mathrm{}$ grown by oxygen-plasma-assisted molecular-beam epitaxy at emission angles chosen to enhance bulk and surface contributions. We quantitatively reproduce the subtle line-shape differences in these spectra by taking into account the break in symmetry and change in crystal field splitting generated by the presence of the surface.

• Received 28 February 2001

DOI:https://doi.org/10.1103/PhysRevB.64.205414