A structural refinement with LEED for the Pd(100)-(√5 x √5)R27°-O surface

The re-analysis with LEED for the Pd(1 0 0)-(root5 x root5)R27 degrees -O surface structure confirms the basic model, reported previously by Vu et al. [Surf. Sci. 318 (1994) 129], in which a PdO(0 0 1) overlayer is stacked on to the Pd(1 0 0) surface. The refinement reduces the Pendry R-factor to 0.306, from 0.44 in the earlier study, and the detailed structure at the metal-oxide interface shows evidence for a balancing of interactions compared with requirements for the oxide and metal separately. Pd atoms in the oxide layer have a corrugation estimated at 0.20 Angstrom, and the binding of this layer to the metal induces a substantial rumpling in the interface region, which covers especially the first and second metallic layers with corrugations of 0.45 and 0.15 Angstrom respectively. (C) 2001 Elsevier Science B.V. All rights reserved.