The structure of the p(2×2) tellurium overlayer on the (001) surface of copper investigated by leed

Low-energy electron diffraction (LEED) intensities have been calculated for the p(2 × 2) tellurium overlayer on the (001) surface of copper and compared with measurements. The tellurium atoms are found to sit in the hollow position (coordination number 4) 1.70 ± 0.15 Å above the atomic plane of the uppermost copper layer. This distance corresponds to a copper-tellurium bond length of 2.48 ± 0.10 Å which indicates a value less than 2.65-2.67 Å typical of copper-tellurium bulk compounds. Five different potentials were used for the adsorbate atoms and a potential from overlap of atomic charge densities with the Kohn-Sham-Gaspar expression for the exchange clearly gave the best agreement with experiment.