Dissociative chemisorption of H₂ on Ni surface: Time-dependent quantum dynamics calculation and comparison with experiment

A time-dependent quantum wave packet method has been applied to studying the process of activated dissociative chemisorption of H₂ on Ni( 100) surface. The Ni surface is treated as static and the effect of weak surface correlation is neglected in our dynamics calculation. The three-dimensional calculation is fully quantum mechanical without any reduced dimension approximation. An empirical London-Erying-Polanyi-Sato (LEPS) potential surface has been used and modified in our dynamics calculation to produce a reasonable barrier height compatible with experiment. Sticking probabilities have been computed as a function of initial normal incident kinetic energy and are compared to experimental results as well as another 3D quantum dynamics calculation. Good agreement has been found between our theoretical calculation and molecular beam experiment in the energy dependence of the dissociation probability. It is also found that vibrational excitation of H₂ enhances dissociation probability, in agreement with the prediction of an earlier theoretical calculation. Snapshots of the wave function are plotted that provide intimate details of the dissociation dynamics in time and space.