[Zurück]

E. Zaki, Z. Jakub, F. Mirabella, G. Parkinson, S. Shaikhutdinov, H. Freund:
"Water ordering on the magnetite Fe_{3}O_{4} surfaces";
Journal of Physical Chemistry Letters, 10 (2019), S. 2487 - 2497.

The interaction of water with the most prominent surfaces of Fe3O4,(001) and (111), is directly compared using a combination of temperature-programmed desorption, temperature-programmed low energy electron diffraction(TP LEED), and scanning probe microscopies. Adsorption on the (√2×√2)R45°-reconstructed surface of Fe3O4(001) is strongly influenced by the surfacereconstruction, which remains intact at all coverages. Close to the completion of thefirst monolayer, however, the ad-layer adopts a longer-range (2×2) superstructure.Thisfinding is discussed in the context of a similar (2×2) superstructure recentlyobserved on the (111) facet, which exists over a significantly larger range oftemperatures and coverages. In both cases, the long-range order is evidence thatwater−water interactions exert a significant influence on the structure already priorto the nucleation of the second layer. We conclude that the stability differences stem from the smaller unit cell on the (111)surface, and the ability of water to more easily form stable hexagonal ice-like structures on the hexagonal substrate.

http://dx.doi.org/10.1021/acs.jpclett.9b00773