A THEORETICAL-STUDY OF THE CHEMISORPTION OF METHANE ON A NI(100) SURFACE

The dissociative chemisorption of methane at an on-top site on a Ni(100) surface has been studied using a cluster model at the ab initio CASSCF-CI level. In all cases the Ni atom interacting directly with the adsorbate was described at the all-electron level, while the remaining metal atoms were described by one-electron effective core potentials. The calculations yield an activation energy barrier of 15-17 kcal/mol. The binding mechanism at the transition state is discussed.