REACTION PATH FOR THE DISSOCIATIVE ADSORPTION OF HYDROGEN ON THE (100) SURFACES OF FACE-CENTERED-CUBIC TRANSITION METALS

Detailed ab-initio local-density-functional studies of the potential-energy surfaces for the dissociative adsorption of hydrogen molecules on the (100) surfaces of face-centered-cubic transition and noble metals are presented. We show that the energetically most favorable reaction path is determined by quantum-mechanical steering effects arising from the formation and modification of covalent metal–hydrogen bonds. Variations of the local chemical reactivity with the filling of the d-band are discussed at the example of rhodium, palladium and silver surfaces.