Role of dynamic trapping in H2 dissociation and reflection on Pd surfaces

We present results of classical trajectory calculations on dissociative adsorption and reflection of H2 impinging on a frozen Pd(110) surface. The six-dimensional potential energy surface is obtained by interpolation of density functional theory (DFT) calculations using the corrugation reducing procedure. The comparison with earlier work for H2/Pd(111) shows that DFT calculations predict that the Pd(110) surface, though more open, is less reactive than the Pd(111) one. This lower reactivity is associated with a more prominent role of dynamic trapping, at low energies, and with the fact that trapping may end up in reflection as well as in dissociation.