The adsorption of oxygen on (100) and (111) surfaces was studied using high-resolution electron energy loss spectroscopy. In the spectra of the clean (100) surface, only one peak at 14meV was observed, while two intense peaks appeared at 16 and 27meV in the spectra of the clean (111) surface. Oxygen adsorption on the (111) surface was quite different from the (100) surface: oxygen attacks the surface framework of boron on the (111) surface even at room temperature, resulting in the formation of a complex structure including B-O bonds, while the superstructure with only La-O bonds was formed on the (100) surface at room temperature. Only after heating to above 700C, a B-O bond was formed on the (100) surface.

Oxygen Adsorption on LaB6 (100) and (111) Surfaces. Yamamoto, N., Rokuta, E., Hasegawa, Y., Nagao, T., Trenary, M., Oshima, C., Otani, S.: Surface Science, 1996, 357-358, 708-11