SCATTERING OF FAST N-2 FROM PD(111) - A CLASSICAL TRAJECTORY STUDY

Molecular nitrogen is well known for its chemical inactivity. Experime ntal results for grazing incidence N-2 scattering from Pd(111) surface s in the keV range also reveal negligible influences of electronical p rocesses on molecular fragmentation. Therefore, we carry out gn approp riate classical treatment of this system. The N-2-Pd(111) interaction is mediated by an analytical six-dimensional potential energy surface, based on ab initio density-functional-theory calculations and-empiric al data. The molecule-surface interaction seems to be strongly influen ced by the azimuthal direction of incidence as well as the molecular a xis orientation. Particularly, the fragmentation is found to be mainly due to vibrational excitation for highly indexed azimuthal directions , whereas for incidence along lowly indexed directions rotational exci tation is more important. (C) 1997 American Institute of Physics.