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B. Arndt, R. Bliem, O. Gamba Vasquez, J. van der Hoeven, H. Noei, U. Diebold, G. Parkinson, A. Stierle:
"Atomic structure and stability of magnetite Fe₃O₄(001): an x-ray view";
Surface Science, 653 (2016), 76 - 81.

The structure of the Fe3O4(001) surface was studied using surface X-ray diffraction in both ultra-high
vacuum, and higher-pressure environments relevant to water-gas shift catalysis. The experimental X-ray
structure factors from the
√
2x
√
2 R 45◦ reconstructed surface are found to be in excellent agreement with
the recently proposed subsurface cation vacancy (SCV) model for this surface (Science 346 (2014), 1215).
Further refinement of the structure results in small displacements of the iron atoms in the first three double
layers compared to structural parameters deduced from LEED I-V experiments and DFT calculations.
An alternative, previously proposed structure, based on a distorted bulk truncation (DBT), is conclusively
ruled out. The lifting of the
√
2 ×
√
2 R 45◦ reconstruction upon exposure to water vapor in the mbar pressure
regime was studied at different temperatures under flow conditions, and a roughening of the surface
was observed. Addition of CO flow did not further change the roughness perpendicular to the surface but
decreased the lateral correlations.