Dissociative adsorption of H2 on Ni(111)

摘要: Ab initio configuration interaction calculations are performed to study the dissociative adsorption of H2 on a Ni(111) surface. The lattice is modeled as an embedded three‐layer 41‐atom cluster. Ni 3d orbitals explicitly included seven atoms H preferentially chemisorbed at threefold site and calculated binding energy 62 kcal/mol, H–Ni distance 1.86 A, vibrational frequency 1176 cm−1 in excellent agreement with experimental data. adsorbed bridge on‐top sites 2.5 8.1 kcal/mol less stable, respectively. heat reaction (gas)→2 (ads) be 22.0 exothermic. When two nearest neighbors same atom, preferred fcc–fcc, hcp–hcp, or across atom fcc–hcp sites. These structures consistent observed (2×2)−2H low electron diffraction pattern. average per f...