The Theoretical and Computational Chemistry Program of the Chemistry Division has provided support to Professor Zhang to use a novel computational method to conduct two studies in the general area of chemical dynamics: (1) a study of dissociative adsorption and associative desorption of hydrogen on transition metals, and (2) an investigation of the rotational state distribution in the vibrational predissociation of the HF dimer. The work involves massive computations made possible by a combination of recent advances in computer technology and a new time-dependent quantum wave packet method that has been developed by Professor Zhang. %%% The breaking apart of molecules as they are adsorbed on a surface or their recombination as they leave the surface are two of the fundamental steps in catalytic processes. In this research, Professor Zhang applies a new technique he has developed to make possible a more realistic study of such individual chemical steps than has previously been possible. The present work is limited to hydrogen as the adsorbing gas, but it will serve as a test of the new theoretical advances which may be applied to larger systems later as computer technology advances. The same theoretical approach is also being used and further tested in a study of the energy distribution in the products when the hydrogen bond in the HF dimer is broken.