H2 dissociative adsorption on Mg, Ti, Ni, Pd and La Surfaces

We calculate the corresponding two-dimensional (2D) potential energy surfaces (PESs) for one fixed lateral H2 center of mass position and one H2 orientation on Mg(0 0 0 1), Ti(0 0 0 1) Ni(1 1 1), Pd(1 1 1) and La(0 0 0 1) surfaces within the density functional theory. From the results, on the Ti, Ni, Pd and La surfaces, the energy barriers for H2 dissociative adsorption are either small or negligible. On the other hand, on the Mg surface, a high energy barrier exists. Furthermore, we can practically explain these differences among the surfaces by considering the differences in the valence electron configurations of the substrate atoms.