The methanethiolate-induced pseudo-(1Â 0Â 0) reconstruction of Cu(1Â 1Â 1): A medium energy ion scattering structure study

The pseudo-(1 0 0) reconstructed surface of Cu(1 1 1) induced by adsorbed methanethiolate, CH3S-, has been investigated by medium energy ion scattering (MEIS) using 91 keV incident H+ ions with the objective of establishing the number of reconstructed Cu layers. The results are shown to be consistent with a single reconstructed Cu surface layer containing 0.66 ML Cu atoms in an incommensurate or long-range coincidence net structure. Specifically, excellent fits to both the scattered ion energy spectra and the angular blocking curves are found for a model based on a single pseudo-(1 0 0) reconstructed Cu layer, the atomic density being consistent with that proposed in an earlier STM study (S.M. Driver, D.P. Woodruff, Surf. Sci. 457 (2000) 11).