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Jahn-Teller stabilization of a "polar" metal oxide surface: Fe3O4(001)

R. Pentcheva·F. Wendler·H. L. Meyerheim·W. Moritz·N. Jedrecy·M. Scheffler
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Abstract

Using ab initio thermodynamics we compile a phase diagram for the surface of Fe3O4(001) as a function of temperature and oxygen pressures. A hitherto ignored polar termination with octahedral iron and oxygen forming a wave-like structure along the [110]-direction is identified as the lowest energy configuration over a broad range of oxygen gas-phase conditions. This novel geometry is confirmed in a x-ray diffraction analysis. The stabilization of the Fe3O4(001)-surface goes together with dramatic changes in the electronic and magnetic properties, e.g., a halfmetal-to-metal transition.

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R. Pentcheva, F. Wendler, H. L. Meyerheim, W. Moritz, N. Jedrecy, M. Scheffler. 2005-01-17. Jahn-Teller stabilization of a "polar" metal oxide surface: Fe3O4(001). https://doi.org/10.1103/physrevlett.94.126101

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