Coverage-dependent adsorption sites in the K/Ru(OOOl} system: a low-energy electron-distraction analysis
نویسندگان
چکیده
The two ordered phases p(2 X 2) at a coverage 6’ = 0.25 and ifi X fi)R30” at 6 = 0.33 of potassium adsorbed on Ru(O~l) were analyzed by use of low-energy electron-diffraction (LEED). In the (A x fiJR30” phase, the K atoms occupy threefold hcp sites, while in the p(2 x 2) phase the fee site is favoured. In both phases, the K hard-sphere radii are nearly the same and close to the covalent Pauling radius.
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