Low-energy electron diffraction patterns from K-adsorbed (001) surfaces were studied, as a function of coverage, at room temperature and at about 100K. It was found that the hexagonal structure of the clean surface successively changed to a 1 x 1 and to a 1 x 2 structure with increasing coverage at room temperature. The 1 x 2 pattern was explained by assuming reconstruction of the substrate (001) surface. The 1 x 2 reconstructed surface was thought to adopt a missing-row type of structure. This suggestion was supported by the K-coverage dependence of the work function change.

M.Okada, H.Iwai, R.Klauser, Y.Murata: Journal of Physics - Condensed Matter, 1992, 4[44], L593-600