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arXiv · 2308.12023

Oxygen-Terminated (1x1) Reconstruction of Reduced Magnetite Fe$_3$O$_4$(111)

Florian Kraushofer·Matthias Meier·Zdeněk Jakub·Johanna Hütner·Jan Balajka·Jan Hulva·Michael Schmid·Cesare Franchini·Ulrike Diebold·Gareth S. Parkinson
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Abstract

The (111) facet of magnetite (Fe$_3$O$_4$) has been studied extensively by experimental and theoretical methods, but controversy remains regarding the structure of its low-energy surface terminations. Using density functional theory (DFT) computations, we demonstrate three reconstructions that are more favorable than the accepted Fe$_{\rm oct2}$ termination in reducing conditions. All three structures change the coordination of iron in the kagome Fe$_{\rm oct1}$ layer to tetrahedral. With atomically-resolved microscopy techniques, we show that the termination that coexists with the Fe$_{\rm tet1}$ termination consists of tetrahedral iron capped by three-fold coordinated oxygen atoms. This structure explains the inert nature of the reduced patches.

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Florian Kraushofer, Matthias Meier, Zdeněk Jakub, Johanna Hütner, Jan Balajka, Jan Hulva, Michael Schmid, Cesare Franchini, Ulrike Diebold, Gareth S. Parkinson. 2023-08-23. Oxygen-Terminated (1x1) Reconstruction of Reduced Magnetite Fe$_3$O$_4$(111). https://doi.org/10.1021/acs.jpclett.3c00281

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