Electronic and atomic structure of clean and oxidized FeAl(110) surface
Abstract
The electronic and atomic structure of clean and ultra-thin alumina on FeAl(110)surface has been studied with photoemission spectroscopy and STM. Previous studies indicate that the atomic structure and composition within the surface region of this intermetallic alloy varies strongly with annealing temperature. At low annealing temperatures (675 K), the valence electronic structure of the (1x1) surface is dominated by Fe d-band features within 3 eV binding energy. Upon annealing to 1125 K, STM and LEED indicate the formation of reconstructed, incommensurate FeAl2 composition at the surface. Photoemission spectroscopy reveals that an enhanced density of states at EF and angle-dependent Fe-3p and Al-2p core-level spectroscopy indicates an Al-rich surface due to preferential surface segregation. STM and LEED reveal that upon exposure of a saturation coverage of oxygen (1000 L at 1125 K), an ultra-thin film ( ∼ 0.6 nm) of alumina forms at the surface, resulting in a large superstructure. Photoemission spectroscopy reveals a strong attenuation of DOS at EF and metallic Al-2p core and emergence of 2p oxygen structure in valence and oxide Al-2p shifted core ( ∼2.6 eV).
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2003
- Bibcode:
- 2003APS..MARS33012K