Six-dimensional quantum dynamics of scattering of (v=0, j=0) H-2 from Pt(111): comparison to experiment and to classical dynamics results

We present six-dimensional quantum and classical dynamics calculations on t he dissociative chemisorption of (upsilon = 0, j = 0) H-2 on Pt(1 1 1) at n ormal incidence. The potential energy surface (PES) used is based on points computed with density functional theory (DFT), employing the generalized g radient approximation and a slab representation of the metal surface. A cor rugation-reducing procedure was used to obtain the PES by interpolating the DFT results. The quantum results are in good agreement with recent molecul ar beam experiments. For the activated system considered, the quasi-classic al method works better than the classical method, the quasi-classical resul ts being in excellent agreement with the quantum results. (C) 2001 Elsevier Science B.V. All rights reserved.