Low-energy electron diffraction was used to determine the adsorption geometry of the ordered p(2 x 2) potassium overlayer on the (potassium-induced) (1 x 2) missing-row reconstruction of Cu(110) at 47K. The K adsorption site in this ordered structure was substitutional, whereby the K atoms occupy half of the Cu sites which were vacated in the missing-row reconstruction. The distance between the K atom and its nearest neighbours (in the second Cu layer) was 3.24Å. Very little lateral displacement of the second-layer Cu atoms was observed, but there was a significant buckling in the third layer. The effect of this buckling was to pull the rows of third-layer Cu atoms which were directly beneath the K rows towards the surface, thus increasing the effective coordination of the K atoms.

LEED Study of the potassium-Induced Reconstruction of Cu(110). N.Ferralis, M.Caragiu, K.J.Franke, R.D.Diehl: Journal of Physics - Condensed Matter, 2001, 13[18], 3961-7