Previous articles had attempted to determine the surface composition and structure of the (2 x 2)p4g phase induced by one monolayer of Pd deposition at room temperature onto a Cu(001) surface. In order to remove inconsistencies arising from previous studies, the 1ML Pd/Cu(001) surface was re-investigated using low-energy ion scattering, low-energy electron diffraction, 3-dimensional classical scattering simulations and embedded-atom method calculations. Using Li+ and He+ ion scattering with calibration measurements on reference samples of Cu(001) and Pd(001), the surface Pd composition of the 1ML phase was independently determined to be 53% and 51%, respectively. The results obtained using K+ ion scattering, low-energy electron diffraction and computer simulations were consistent with a surface structure which consisted of 30% of a clock-rotated (001) Pd phase and 70% of an unreconstructed p(2 x 2) Cu-Pd phase. The stability of the (2 x 2)p4g phase was confirmed by embedded-atom method calculations.

Reinvestigation of the Surface Reconstruction of Cu(001)-(2 x 2)p4g-Pd. Y.G.Shen, A.Bilic, D.J.O'Connor, B.V.King: Surface Science, 1997, 394[1-3], L131-7