Dissociative chemisorption of H2 on Pt(111):: isotope effect and effects of the rotational distribution and energy dispersion

Six-dimensional quantum dynamics calculations on dissociative scattering of H-2 and D-2 from Pt(111) are performed. The six-dimensional potential energy surface used was generated using density functional theory employing the generalized gradient approximation. The isotope effect, the effect of widening the rotational distribution on the dissociation probability and the effect of the energy dispersion are investigated, as they are possible reasons for a discrepancy between previous theoretical work and molecular beam experiments. It was found that these effects cannot explain the differences between the theoretical and experimental results. (C) 2004 Elsevier B.V. All rights reserved.