Abstract
We performed a systematic full-potential density functional theory study with the generalized gradient and local density approaches on five possible terminations of the low-index polar (111) surface of . Applying the concepts of first-principles thermodynamics, we analyze the composition, the structure, and the stability of the (111) orientation at equilibrium with an arbitrary oxygen environment. The densities of states of the unrelaxed and relaxed (111) surfaces were calculated and compared with that of bulk . The calculations reveal that the -terminated surface is energetically favored, showing metallic properties. The -terminated surface is more active than the other two Fe-terminated surfaces, showing half-metallic properties, similar to bulk . The -terminated surface, the O-terminated surfaces, and the surfaces with vacancy defects all show metallic properties.
- Received 26 October 2005
DOI:https://doi.org/10.1103/PhysRevB.74.035409
©2006 American Physical Society