Dissociation of fast N2 molecules at a Pd(110) surface

The Pd(110) surface has been chosen to study the dissociation of fast nitrogen molecules with kinetic energies in the range from 300 eV per atom to 1500 eV per atom, scattered under grazing incidence. At such high energies, the dissociation is understood to be caused by vibrational and rotational excitation, the latter bring favoured for scattering along surface semi-channels. The Pd(110) surface provides channels with different structures and widths. We find that the dissociation probability of the molecules increases when going from the [1 (1) over bar 2] to the [1 (1) over bar 1] and the [1 (1) over bar 0] directions, respectively. Our experimental results are compared with model calculations based on DFT potentials for the Pd-N and Pd-N, interactions. (C) 1998 Elsevier Science B.V. All rights reserved.