An STM and DFT study of the ordered structures of NO on Pd(1 1 1)

Adsorption of NO on Pd(1 1 1) has been studied by scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. Three ordered structures, c(4×2), c(8×2) and p(2×2), were observed by STM in the temperature interval 170–300 K. Adsorption sites have been assigned on the basis of the DFT calculations, which also explain the coexistence of the three phases, observed by STM. It is shown that a repulsive adsorbate–adsorbate interaction is mediated by the substrate and the interaction is described quantitatively.