engleski

SUBSTRATE RELAXATIONS IN CO CHEMISORPTION ON Pt(111) SURFACE

We have performed density functional (DFT) calculations of CO chemisorbed on a Pt(111) surface at a coverage of 0.25, for various chemisorption sites and geometries. Besides the total energy, we calculated the forces acting on the surrounding substrate atoms before these are allowed to relax. We find that the adsorption into hollow sites is energetically favoured, in agreement with some recent calculations but in disagreement with experimental findings which prefer the on-top sites. The forces on the neighbouring substrate atoms are quite large when allowed by symmetry, and may contribute to stabilizing the on-top adsorbates at low coverages and lead to strong adsorbate-adsorbate interactions.

density functional theory; chemisorption; substrate relaxation; carbon monoxide; platinum

nije evidentirano