PERFORMANCE OF CLOSE-COUPLED WAVE-PACKET METHODS FOR MOLECULE-CORRUGATED SURFACE SCATTERING

The H-2 + LiF(001) system was used to investigate the performance of the hybrid close-coupling wave packet (CCWP) method and of a symmetry adapted, fully close-coupled wave packet (SAWP) method for a molecule-surface problem characterized by fairly high corrugation. In the calculations, a realistic, phi-dependent model potential was used. The calculations were performed for a collision energy of 0.2 eV, with H-2 initially in its j=0 rotational state at normal incidence to the surface, Large increases in the computational efficiencies of both wave packet methods were achieved by taking advantage of the potential coupling matrices associated with both methods becoming sparser with increasing molecule-surface distance. For the present model problem and employing this increased sparseness at longer range, the SAWP method is faster than the CCWP method by a factor of 2. The potential usefulness of the SAWP method for dissociative chemisorption problems is discussed. (C) 1995 American Institute of Physics.